One of this year's more surprising and impressive music-biz successes is surely that of The Traveling Wilburys, whose 2CD/DVD compilation The Traveling Wilburys Collection entered the album chart this week at No 1, outselling the likes of Bon Jovi, Paul McCartney and Queens of the Stone Age, and turfing the lissom R&B diva Rihanna off the top spot. Indeed, it may be the only album this year to reach this level of success without the assistance of MySpace, YouTube or any of the internet-associated aids which, we are constantly told, are vital promotional tools in today's pop marketplace.

But then, what might be on their MySpace site? "Hi kids, we're The Traveling Wilburys! We're old enough to be your grandads - in fact, two of us are so old we're dead, and the rest aren't feeling too good at the moment. We make the kind of music you probably hate."

Their MySpace friends, however, would number in the hundreds of millions, comprising as they would the combined fan-bases of The Beatles, Bob Dylan, Roy Orbison, ELO and Tom Petty & The Heartbreakers. (Of course, this reissue has sparked both YouTube and MySpace activity, though judging by the usual parade of sad self-publicists who attach themselves to such sites, the Wilburys are not vetting those who claim their friendship.)

With hindsight, however, it's possible to discern the factors underlying the Wilburys' current success. Since the release of their debut album in 1988, the "dad rock" phenomenon has become a force in music sales as ageing baby-boomers and Sixties kids refused to abandon their interest in rock, bringing the weight of their huge disposable income to bear on both the charts and the media.

The rise of mature music magazines such as Mojo, Uncut and The Word has been paralleled even in the staid world of BBC radio by the re-branding of Radio 2 as a sort of Sixties' oldies station, whose regard for pop heritage and roots is balanced by its eye for what's currently hip. And The Traveling Wilburys, Vol 1 may be the perfect Radio 2 record, featuring as it does five well-known, respected talents of a certain age, each wielding serious industry clout and historical weight, peddling a bunch of jaunty, singalong songs rooted in the mulch of rock'n'roll heritage and performed with the minimum of synthetic studio assistance and the maximum amount of harmonies that can be crammed into 10 tracks.

It's a sort of Sing Something Simple formula for another generation, except that these Wilburys are also songwriters skilled enough to write new songs that promptly take up residence in one's memory like old friends, whether you want them to or not. Hearing songs such as "Handle With Care" and "End of the Line" for the first time, many listeners were struck by just how familiar they sounded, as if they were cover versions of classic hits.

And of course, in a sense they were: to ears that grew up on Dylan, Orbison, ELO and The Beatles, not to mention the wealth of influences, from Buddy Holly to The Byrds, that course through Tom Petty's work - their chord changes, intervals, harmonies and melodic tropes tapped into a host of comforting memories, like endorphins slotting into an addict's neuroreceptors. The result was pure pleasure, unmediated by the constraints of fashion or duty. The album went on to sell some five million copies, making it the most successful "supergroup" album of all time.

The pop supergroup has something of a chequered history, which helps to prepare one for the disappointment that often attends the actual music. The idea derives from jazz, where individual players would combine and re-combine in different aggregations for purely exploratory purposes, to see how they might push each other's performances in new directions. The most famous are probably Miles Davis's two quintets that aligned the trumpeter with the likes of John Coltrane, Herbie Hancock, Cannonball Adderley and Wayne Shorter, and the great bebop summit of Charlie Parker, Dizzy Gillespie, Bud Powell, Charles Mingus and Max Roach that produced the legendary Massey Hall concert of 1953.

The first rock'n'roll supergroup was undoubtedly the impromptu meeting of Elvis Presley, Johnny Cash, Carl Perkins and Jerry Lee Lewis at Sun Studios, the off-the-cuff recordings of which were released under the bullish - but ultimately undervaluing - rubric of The Million Dollar Quartet.

Through the Sixties, supergroups hatched, flew briefly and then died, like mayflies seeking mates. Session musicians like Al Kooper and Mike Bloomfield were elevated to serious player status by their "supersession" jams, while authentic stars like Clapton, Baker, Bruce and Winwood became global icons through the success of Cream and the deeply underwhelming Blind Faith project. For a while in the Seventies, Crosby, Stills, Nash & Young were the biggest-selling group in the world.

Even the more marginal music genres threw up their own supergroups, most notably the Pentangle aggregation, which combined virtuoso folk guitarists Bert Jansch and John Renbourn with singer Jacqui McShee and the jazz rhythm section of Danny Thompson and Terry Cox.

But the rock supergroup quickly became a byword for ego, excess and interminable soloing, most spectacularly in the case of Emerson, Lake & Palmer, a prog-tastic alliance whose stodgy, quasi-classical music filled stadiums, but not souls.

With the advent of punk, the supergroup's days were numbered; the notion became not just musically dubious, but a representation of the morally reprehensible separation of artists from their audiences. Now, as Andy Warhol and Sly Stone had claimed, everybody was a star, and to profess one's superiority was just about the only form of bad manners recognised by the punk movement.

For a decade or so, the supergroup fell out of favour, along with the idea of virtuosity. Outside America, the accent in the Eighties was more on amateurism and unashamed artifice, whether as ironic commentary on the business of pop, or as celebration of its sleek, flimsy surfaces. The only significant supergroup projects were charity one-offs like Band Aid's " Do They Know It's Christmas?", in which the participants' names mattered rather more than their musical abilities. Save for the Wilburys, that has remained the case ever since, as each new disaster prompts its own charity record.

So, when the Wilburys got together in 1988, few notions were as utterly discredited as that of the supergroup, which may be a contributory reason for the players' pseudonyms: Nelson (George Harrison), Lucky (Bob Dylan), Lefty (Roy Orbison), Otis (Jeff Lynne) and Charlie T Wilbury Jr (Tom Petty). The group's genesis came when Harrison was trying to come up with a new B side to "This Is Love", the single from his Cloud Nine album. He contacted his chum Lynne, who was working with Orbison on the latter's Mystery Girl album, and persuaded both of them to lend a hand. When George visited Tom Petty to reappropriate a borrowed guitar he wished to use, Petty was roped in, swiftly followed by Dylan.

"And so everybody was there," Harrison recalled later, "and I thought, 'I'm not gonna just sing it myself, I've got Roy Orbison standing there - I'm gonna write a bit for Roy to sing.' And then as it progressed, I thought I might as well push it a bit and get Tom and Bob to sing the bridge. "

When Warner Brothers head Mo Ostin and A&R chief Lenny Waronker heard the resulting "Handle With Care", complete with the contributions from George's heavy friends, they realised that it was too good to languish on the flip side and manoeuvred for an entire album by the group.

With all members bar Orbison contributing songs, the album was completed within three weeks in a makeshift studio erected in Dave Stewart's kitchen in Los Angeles. Its relaxed, genial tone is indicative of the low-pressure nature of the sessions. Harrison's "Handle With Care" and " End of the Line" were the obvious standout tracks, both charting as singles. Dylan's trio of songs highlighted his various strengths: " Congratulations" was a melancholy heartbreak anthem and "Tweeter and the Monkey Man" a typical shaggy-dog-story street-life narrative, while "Dirty World" offered a surprisingly serviceable variation on the standard rock'n'roll automotive sexual metaphor, the tangle-haired bard indulging in saucy flattery such as "You don't need no wax job/ You're smooth enough for me" before the rest of the band chipped in their cryptic commendations.

Lynne's production nous ensured that none of the individual players was favoured, and Petty's talent for cementing styles together proved invaluable throughout. Orbison, meanwhile, was a magisterial presence, his operatic grace lending a classy, high-gloss finish to performances that were, in effect, enthusiastic and affectionate celebrations of the musicians' roots in rockabilly, hootenanny and skiffle.

Like the album packaging and parodic sleevenotes (by "Hugh Jampton, the EF Norti-Bitz Reader In Applied Jacket, University of Krakatoa", aka George's Pythonic chum Michael Palin), the band's name was a light-hearted trifle, deriving from a studio in-joke of Lynne and Harrison's, referring either to effects devices they dubbed "wilburys", as in " trembling wilbury", or to the use of such devices at a project's mix-down stage, as in "we'll bury it in the mix". Trembling, it was subsequently decided, was a less attractive prospect than Traveling. Advance promotion, meanwhile, was restricted to little more than a few postcards proclaiming "The Traveling Wilburys are coming!" over sepia photos of eccentric modes of transport, an understated campaign that gave no hint of the project's genealogy, nor its ultimate sales success.

Despite the minimal promotional work, and the lack of live performances to support it, the first album shifted five million units, a considerable improvement on the individual members' flagging sales profiles at that point. A follow-up was unavoidable, but shortly after the debut's appearance, Roy Orbison died. Rumours that Del Shannon was to replace him proved unfounded, and any prospect was ultimately dashed by the singer's suicide; in the end, the four remaining Wilburys - now re-named Spike (George), Boo (Bob), Clayton (Jeff) and Muddy (Tom) - dedicated the second album, Vol 3, to their late pal Lefty.

This follow-up album was both heavier and more refined than the debut, while the participants were less afraid to damage their individual reputations: Dylan, for instance, incorporated a hilarious scatted refrain in "You Took My Breath Away", and his doowop-styled "Seven Deadly Sins" employed the same kind of nursery-rhyme counting-song lyrical simplicity that he featured on his contemporary Under The Red Sky album. "Cool Dry Place " included an offhand reference to Jeff Lynne's old band The Idle Race, while the opening "She's My Baby" was by far the toughest item in their slim repertoire.

But the lacklustre dance-parody closer "Wilbury Twist" confirmed that the joke was getting rather thin by this point, and Vol 3 proved to be substantially less successful than its predecessor.

Until now, that is. With both Wilburys albums having been deleted with what, considering their lineage, seems indecent haste, a groundswell of interest has built up over the subsequent years. George Harrison's plans to reissue remastered versions of the albums were scuppered by his passing, but his widow Olivia has helped to ensure that his wishes have finally been realised.

Ironically, the albums sound less out of step with current trends than they did on their original release, suggesting that the Wilburys have perhaps exerted a much greater influence in the intervening years than had ever seemed likely on their first appearance.

Wanna be in my band? The world's greatest supergroups

ELECTRONIC

FORMED 1989

One of the first post-punk supergroups, Electronic were the on-off project formed by New Order's Bernard Sumner and Smiths guitarist Johnny Marr. Neil Tennant of the Pet Shop Boys joined Sumner on vocals for the debut single " Getting Away With It", but the record didn't make the UK top 10. The second single "Get the Message" appeared in 1991, and an eponymous album followed that year. Marr and Sumner reunited in 1996, joined by Kraftwerk member Karl Bartos and released "Raise the Pressure". A best-of album came out last year.

THE PLASTIC ONO BAND

FORMED 1969

A conceptual supergroup formed of John Lennon and Yoko Ono, plus whoever was performing with them (variously Eric Clapton, Alan White (Yes), the Who's Keith Moon, as well as George Harrison and Ringo Starr), the Plastic Ono Band emerged as the Beatles entered a terminal decline. The only album solely credited to the band, Live Peace in Toronto, 1969, featured Clapton on guitar. Clapton appeared again on "Cold Turkey", a harrowing account of Lennon's brief addiction to heroin. In a sarcastic dig at the establishment, Lennon cited the single's slide down the charts as one of the reasons for handing back his MBE. The last Plastic Ono Band credit was on Lennon's 1975 retrospective compilation Shaved Fish.

BAND AID

FORMED 1984

So moved was Bob Geldof when he saw BBC news reports from famine-stricken Ethiopia that he enlisted the help of the Ultravox front man Midge Ure to produce what became the biggest-selling single of the 1980s. Flicking through his address book, Geldof signed up some of the biggest names in UK music, including Phil Collins, Bono, Simon Le Bon, Paul Weller, George Michael, Sting and David Bowie, to record "Do They Know It's Christmas?" . It stormed to No 1 in the UK, selling a million copies in a week. Geldof followed up a year later with the Live Aid concert. A new version of the song, featuring Kylie, Bros and Bananarama, was released in 1989. In 2004, a 20th anniversary release with a Damien Hirst cover raised millions for famine victims in Darfur.

CREAM

FORMED 1966

Frank Sinatra was top of the charts in July 1966 when Melody Maker announced the formation of a new "group's group". The band, led by supergrouper Eric Clapton (The Yardbirds, John Mayall's Bluesbreakers), with Jack Bruce (Bluesbreakers, Manfred Mann, Graham Bond Organisation) on bass and Ginger Baker (Graham Bond Organisation) on drums, would become rock's first power trio and inspire bands from Black Sabbath to the Smashing Pumpkins. Cream's mix of blues, pop and psychedelia was first aired Fresh Cream, which reached number six in the album charts. The band split in 1968, but rumours abound that they'll re-form.

THE GOOD, THE BAD & THE QUEEN

FORMED 2007

Blur frontman Damon Albarn insists his latest endeavour is not in fact a band but a project or, to use his words, "a song cycle that's also a mystery play about London". The group's debut album (its title refers to the people of London) is an alternative rock collaboration between Albarn, Paul Simonon of The Clash, The Verve's Simon Tong and Fela Kuti drummer Tony Allen. The 12-track record received almost uniformly positive reviews and in an interview with NME last March, Albarn announced plans to produce a "totally different, more funky" record this autumn.

CROSBY, STILLS & NASH (AND YOUNG)

FORMED 1968

Known for their distinctive vocal harmonies and political activism, CSN(Y) comprised elements of The Hollies, The Byrds and the disbanded Buffalo Springfield. Nash joined Crosby and Stills after quitting The Hollies and the trio were snapped up by Atlantic Records. They then signed Neil Young, another Buffalo Springfield alumnus, in 1969. Their debut album Déjà Vu was a huge success, after a landmark performance at Woodstock. All members signed lucrative solo deals, but CSNY continued to perform.

EMERSON, LAKE & PALMER

FORMED 1970

ELP almost became HELP when in 1970 Jim Hendrix considered joining the band, but the rock guitar legend was found dead weeks later, leaving Emerson (The Nice), Lake (King Crimson) and Palmer (Atomic Rooster) to go it alone. Their eponymous debut album sold thousands and they sealed their place in the supergroup hall of fame at the 1970 Isle of Wight Festival. Changing tastes in the late 1970s saw ELP's demise and musical differences led to a split. They became Emerson, Lake and Powell in 1985 when Cozy Powell appeared on an album. The original ELP briefly reformed in the late 1990s but have since focused on solo projects.

THE EAGLES

FORMED 1971

Drawing influence from traditional rock'n'roll, the Eagles' early sound was a hybrid of country and bluegrass instrumentation, coupled with harmonies of West Coast surfer rock. It helped define what became known as classic rock and saw the band become one of the most successful groups of the 1970s and the bestselling US group of all time. Hotel California and Their Greatest Hits 1971-1975 both rank in the top 10 highest selling albums in the United States. With a changing line up of four or five artists, the band now comprises founding members Glen Frey and Don Henley alongside the James Gang guitarist Joe Walsh and Poco's Timothy B Schmit. After an eight-year hiatus the Eagles reformed in 1994 and were expected this year to release their first album of new music in almost 30 years.

ASIA

FORMED 1981

Featuring King Crimson bassist and vocalist John Wetton, ELP drummer Carl Palmer, keyboardist Geoff Downes from Buggles, with Steve Howe (Yes) on guitar, Asia were the logical successor to 1970s progressive rock bands. Their foundation in 1981 coincided with the launch of MTV. Downes's hit song with The Buggles, "Video Killed The Radio Star", was the first song played on the channel and, during the early 1980s, Asia and MTV became instrumental in each other's success. A string of creative differences and changes in personnel followed, but the band still performs and is expected to release a new album next year.

THE HIGHWAYMEN

FORMED 1985

The Highwaymen were to country music what the Wilburys were to rock'n'roll. Featuring Johnny Cash, Willie Nelson, Waylon Jennings and Kris Kristofferson, their first single in 1985 topped the US country charts and led to the album Highwayman. A second album, Highwayman 2, failed to repeat the success. The group's last release, The Road Goes On Forever (1995), passed without fanfare; they didn't record again. Jennings died in 2002.

Compiled by Simon Usbourne