Opener is a game devised by Tom Russotti. Tom has created The Institute for Aesthletics ( an organization dedicated to the playing of sports as an artistic practice)....check out his website here
His new game of Opener (seen in the video below) is a team game where each player wears a helmet with a hula hoop attached (easily achieved with a cycling helmet and some gaffer tape) that makes them look a little like a giant bottle opener..hence the game's name.
Teams pass a ball between themselves by throwing or kicking with the aim being to get into the opponent's end zone and once there throw it through one of their own team's helmet hoops. If they do this then a point is scored. Obviously the other team constantly try to intercept and get the ball down to the other end and do likewise.
Full contact is allowed.