The most beautiful "humorous" opening trap for me is this one (the game is played by correspondence Chess, but unfortunately, i don't remember the Players...but it's real!!) :
1.d4 Nf6 2.c4 g6
After this move, the player with the black pieces say: on any move played by White, i would continue by 3...,Bg7.
Do you find the move for White ?
That's the problem with premoves.
Here's a nice one that occured in one of my games: