A motorist who tweeted about "bloody cyclists" after a collision described the post as "my biggest regret" as she was convicted of driving offences.
Former trainee accountant Emma Way, 22, from Watton, Norfolk, was found guilty at Norwich Magistrates' Court today of failing to stop after a collision and failing to report an accident .
She was cleared of driving without due care and attention.
Magistrates heard that police only became aware of the collision on May 19 because Miss Way tweeted "definitely knocked a cyclist off his bike earlier. I have right of way - he doesn't even pay road tax!" using the hashtag #bloodycyclists afterwards.
Cyclist Toby Hockley suffered bruising and minor damage to his bike in the incident near the village of Rockland All Saints, Norfolk.
Magistrate Martin Cliffe fined Way £337 and ordered her to pay £300 in costs. He also ordered that seven penalty points be added to her licence.
Way told the court that she had lost her job with Norwich-based accountancy firm Larking Gowen as a result of the tweet.
She said: "The tweet was spur of the moment. It was ridiculous and stupid and I apologise to all cyclists.
"It is the biggest regret of my life so far."
Way had about 200 Twitter followers when she sent the message and used to tweet daily.
She said she had since quit the social networking site.
Prosecutor Stephen Poole said Mr Hockley had been cycling around a blind corner at the time of the incident.
Describing the trial as a relatively routine case of driving without due care and attention, he added: "Why it becomes notorious is because the suspect went home and tweeted.
"It was that tweet which has put this into the public arena."
Mr Hockley, a life-long cyclist who covers about 4,500 miles (7,240km) each year, was approaching the end of the 100-mile (161km) Boudicca Sportive with his friend, Jason Sexton, at the time.
"A car came around the corner, narrowly missing Jay," he said.
"The car was heading over to my side of the road.
"I was hit on the leg by the wing and on the arm by the wing mirror and tried to slam on my brakes to regain control."
He said there was a loud crunch and he was knocked into a hedge.
Way told magistrates she had lived near the road for 20 years and had cycled along it as a child.
Claiming the collision was Mr Hockley's fault, she said she had been driving at 15mph and her road positioning was as far to the nearside as possible.
"Afterwards I looked in my mirror," she added.
"I did not think he was injured - if I did I would definitely have stopped."
Way refused to comment as she left court, saying she had signed an exclusive television deal.
Superintendent Dave Marshall, from Norfolk Police, investigated complaints about the tweet.
He said: "Miss Way's online comments did not represent responsible driving behaviour.
"Debates around cycling are often a feature of public meetings and cycle safety is a priority - anyone involved in a collision is required, by law, to stop at the scene.
"Cyclists are also expected to abide by road traffic laws."