How about Ricochet and team tournament modes?

[scaramoosh]

For Ricochet say you have a server of 32 people with 16 games of 1 v 1 going on at once in small arenas. You'll have a leader board that you can move dynamically up and down as you do better or worse. Say you die then you'll play another loser and if you win then you'll move up the leader board and player the loser of a match between the people higher up than you etc etc.

For Team Tournament say you have a server of 20 people, there will be 2 games of 5 v 5 going on at once, the winners and losers of each match go on to play each other.