Really short chess games!
As I was a child I participated in the regional championship of schools several times. During one of these championships I have won a game after 5 moves:
My opponent couldn't believe what happened ;)
In one game against my grandfather there was no early mate but a great advantage of the white player after just a few moves:
There are also some well known very short chess games you might already took notice of:
Perhaps you also know some games, which are over after just a few moves.