I don't feel like posting references, but my favorites would be the Nimzo "Why must I lose to this idiot" outburst, Tony Miles arrested on Downing Street, Rustam Kamsky's intimidation tactics, Azmai's black eye and arrest during the Calvia Chess Olympiad, Rubinstein's "fly", Chucky kicking a concrete pillar, and the guy who sneaked back into the tournament hall and cut off the "heads" of all queens.
I've heard some very vague stories regarding certain eccentricities of top chess players and some of the crazy and outrageous things they've done. For example I've read that Alekhine has more than once urinated in the floor during a chess game. Are such stories true? What are your favorite or most memorable moments in the mentally unstable chess world? I've heard Bobby Fischer often had odd or or outrageous demands to be met before he would play. Also any sort of reference for the validity of such stories would be awesome.