Two men are playing Russian roulette using a pistol with six chambers.
A single bullet is used and the chamber is spun after every turn.
What is the probability that the first man will lose?
(In reply to re(2): A footnote to this problem
Blanks aren't a trivial matter either; actor Jon-Erik Hexum died because of an accident with a gun loaded with blanks.
If I have to go for a PC problem, I'd keep with the "gold coin in box" variation.