Can't stop myself telling this true story here about Stefan Grapelli, as he's been mentioned above a couple of times.
In the late 80's I briefly shared a flat with a guy who was the night chef at a major international hotel here in Melbourne, Australia. He came home one morning as I was going out to work, with this gem. The previous night his night waiter had taken a late order for a meal from a room and on delivering it, saw a violin on the bed.
"Oh, you play the violin, how lovely, I play the violin", the waiter had burbled as he placed the meal on the table. The hotel guest, according to the waiter, had simply smiled and said, "Oh, I play a little", or words to that effect. Absoloutely no grandstanding, no chest beating, no nothing. When the waiter got back to the kitchen he mentioned to my mate Peter the chef that the guests face was vaugely familair. They looked up the current guest/room list. Sure enough: Grapelli, in town for a concert. Peter said the waiter didn't know whether to go back and ask for an autograph or just find a hole in the ground to crawl in to and die of embarrassment there!

Cheers,
John