Tosser is a game not completely unlike rugby, but not actually related to it in any way. Invented in about... ooh, end of 2001 by my friends and constantly improving, it's a game of pain, death, humiliation... yet also glory, not unlike Everything2.
One player swings his/her bag around his/her head and chucks it into the air. Wherever it lands becomes the pile. Everyone playing drops their bag at the pile and the game begins.
One player randomly chooses to become the Tosser. The Tosser's job is to throw a bottle (500ml is best) in any direction as hard as they want. Pretending to wank with the bottle before throwing it is completely optional. Then the game begins. Well, Round One begins.
Everyone playing (except the Tosser, who may not play) then has to gain the bottle by any means necessary (tripping, punching, kicking, attacking with sharp objects, kicking again, grabbing it off them, trickery, and much, much more) and run back with it to the pile. Usually you'll find one or two people running off to get the Bottle wherever it landed, with the rest waiting to attack them as they get close to the pile. Touching the pile with the bottle is a win. There is no scoring system. The winner becomes the new Tosser for Round Two (the old Tosser then goes back to being a normal player) and the game starts over again.
Rule 1. The Player in Possession of the Bottle may not conceal it upon his person.
Rule 2. A Reasonable Gaming Boundary should be set to stop arseholes from just running off and hiding.
Rule 3. The Bottle may not be used as a Weapon (although I break this one all the time, and to be fair, it's only self-defence).
Rule 4. Players must not stay right next to the Pile hoping to grab the Bottle from a player who has gone off and got it - i.e. pile-hanging. (that doesn't sound right.)
Rule 5. Teamplay is forbidden, and pretty crap anyway.
Health Warning - someone broke their wrist playing Tosser once. That's about it, but remember you could be killed playing it, and due to the danger Tosser should not be played by anyone.