I've done most of my own ones but I have ones told me by actor friends... Someone I used to know, a cockney actor so up for all the same roles as him in the 1980s, told me he once went to an audition and Ross Kemp was there, "Talking to himself" apparently (he was probably just learning his lines but my informant was freaked out by it and maybe jealous as Ross probably got the jobs he was up for)!
He told me something about Anthony Hopkins being dragged off a certain film set and bundled into a car to get him off the set, shrieking the most obscene invective you can imagine at the director.
He also said Todd Carty was an egocentric tit but to be fair, he only knew him when they were both young and I suspect that level of fame so early would go to many people's heads. (Unless they're Anthony Head).
He also said he was on set in something with Marianne Faithful and she refused to come out of her trailer much, and they were all briefed not to mention a certain sort of confectionary around her... ;o)
He took me to a party and I was talkiing most of the night to a familiar looking man, I couldn't qutie place. He seemed to enjoy talking with me - in retrospect, probably because it was obvious I had no idea who he was. I still don't know his name as I never watched it, but he was one of the main actors for years in 'The Bill'. He didn't mention 'work' once.
Another actor friend told me that Brian Blessed was lovely - as you'd imagine him. But when he was on set as a glorified extra in a film with Sean Connery they were all told, before he came on set, not to do impersonations or say "Miss Moneypenny"... Apparently he is very up himself.