This video is from a match between two Moroccan teams. Khalid Askri, the goalie playing for Rabat, thought that he had successfully defended his goal. But the spin that he placed on the soccer ball caused it to slowly travel into the net after he had already turned away.
Link via reddit
Except, the rule says the ball is live until the ref calls it dead, when the goalkeeper holds it or is kicked away by a defender or attacker. Completely legal goal.
could have been worse though; see Andres Escobar and the "own goal" that killed him.