I can perform rather complex math in my head very quickly. That's what happens when you go through four years of calculus.
I can drink an unbelievably large amount of Coca-Cola in 24 hours.
I can bend my pinky back so that the tip touches the back of my hand.
I can play Legend of Zelda: Link to the Past and get zero deaths.

Mmmm...I can't think of anymore.