I once DMed a game where a character was played (in DnD) which had a strange kleptomanic compulsion to take things and place them in his box of holding (a small but infinitely large box he carries around). He had been given this box by a wizard who later became an enemy, many sessions after he had recieved it. No one but me and the person playing this character remembered how he got the box, and he judged his character was too dumb to remember himself. Anyway, there's this big final battle against the wizard in his small, claustrophobic tower, and then suddenly the wizard whispers something, the box explodes, and about ten tons of assorted garbage collapses on him, killing him instantly, and doing massive damage to the rest of the party, including launching their rogue into a window, but the magic in his cloak of "feather fall" ended up sparing his life. Anyway, the character who died didn't really lose much, as I thought he played in such good sport (knowing he knew he was going to die) that I let him have a character only a level below the rest of the party (he gathered some new equipment from the tower of the wizard, who was eventually killed in that battle)
