Local celebrities including Nadine Coyle have been raking it in by charging fans more than £40 each for personalised video messages.
The shout-outs from former Girls Aloud singer Nadine and Game of Thrones stars Ian Beattie and Kristian Nairn are advertised on the Cameo website.
The firm says it allows fans to connect with celebs by sending them scripts for personal clips that are mainly gifts for family and friends.
Local stars' videos come in at around £40 a pop, but some big names charge much more.
Rapper Snoop Dogg sells clips at £622.50, Caitlyn Jenner £2,075 and actors such as Chuck Norris, John Cleese, James Van Der Beek and Dolph Lundgren charge more than £200.
Chicago-based Cameo takes a 25 percent commission.
Londonderry-born singer Nadine (35) has three preview videos on the website, all of which show her speaking to fans and blowing kisses to the camera.
The singer, who's worth an estimated £11million, says in one sample clip: "Hello, this is for Jordan and it's a message from your husband Andrew, who wanted to wish you a very special Valentine's Day.
"I hear you have been together for 10 years... it is amazing to be together for that long.
"I hope you have an amazing Valentine's Day and an amazing next 10 years. Loads of love."
Nadine's Cameo profile is now marked 'temporarily unavailable', but Ian and Kristian's are still active. The pop star has just three five-star reviews on the site, while Ian has 125 and Kristian 35.
On his profile, Belfast actor Beattie (55), known for appearing in Game of Thrones, Gangs of London and Oliver Stone's Alexander, describes himself as an "actor, dad, life lover and dog, cat and tortoise owner".
He presents each of his clips as Meryn Trant, his character from Game of Thrones.
In one video he says: "I am Sir Meryn Trant, a true and honourable knight of the King's Guard, and this is a message for you, keeper of chains and father of dragons.
"Your beautiful queen wishes me to send you a message. I can see I have my work cut out for me with this one... happy Father's Day to you, happy Father's Day to you, from my Queen Erica.
"Personally, you may or may not be a jumped-up cut-throat, nothing more, and, of course, Queen Erica is far, far too good for you.
"Nonetheless, I wish you a joyful day, a joyful week, a joyful month, and, in these difficult times, a joyful year."
Beattie, who has had parts in Line of Duty, Vikings and Dr Who, also addresses a "happy naming day" to one fan.
His Lisburn-born Game of Thrones co-star Nairn (44), famous for playing Hodor, has helped bolster the morale of people on the front line during the Covid-19 pandemic with some of his clips.
The DJ and actor tells one devotee: "I believe that you've been promoted to lead blood bank technologist and your whole family are very proud of you.
"I'm sure that you've had a crazy time recently on the front lines of the pandemic.
"I just want to say thank you so much - you have kept the world turning really."
He adds in another video that he "misses how Game Of Thrones brought families and friends together" before the Covid-19 crisis.
It was revealed in April that Fawlty Towers actor Cleese (80) had become a huge hit on Cameo after shooting insult-filled messages for his fans.
It emerged this week that Inbetweeners actor James Buckley was also filming foul-mouthed videos for devotees, delivered in character as Jay Cartwright.
Cameo, which raised £40million in venture capital a year after it launched in 2017, bills itself as the future of the greeting card.
It claims to fulfil around 2,000 video requests daily.