This is headis, a sport played in Germany. Two people face off across a ping pong table, knocking a soccer ball back and forth between them. They can use only their heads to hit the ball.
The video embedded above shows a tournament played in Saarbrucken, Germany this year. I would guess that some of the players are using pseudonyms, unless "Lord Voldehead" and "Nosegrinder" are common given names in Germany.
The best players gradually eliminate the competition until a final champion prevails. Although the sport may sound silly, it clearly requires great dexterity and stamina.
-via Dave Barry