One of the coolest things about PES 2012 is its animation system and a return to its PS2 roots.
An easter egg in Pro Evolution Soccer 2012 allows players to perform Michael Jackson's famous moonwalk as one of their celebration moves. To make your players moonwalk, simply edit one of your players, head over to the movements screen and choose Celebration "91". Your player will perform the famous move whenever he scores a goal.
Here's Messi performing the moonwalk like a pro, although I believe Nani would be a perfect fit for this kind of celebration.