A classic Battle Arena with narrowing borders and a large number of players. Show your skill and destroy other players on the way to becoming the only survivor.
Area of survival shortens as the game progresses; no respawns.
Everybody dies and respawns at specific points on the map, users are rewarded based on relative amount of damage dealt/receive.
Capture the flag, duck hunt, run the labyrinth, etc.
Get points for completing some other activity other than killing opponents (carry the flag, shoot special NPCs, get first to finish), and while the player performs that activity other players collect bonuses over the map.
Every death makes the respawned char stronger, making them harder to kill; can be combined with field shortening.