I just dropped my arena FPS demo on steam.  My goal was to develop a simple and fun multiplayer game that was fun even when you're losing.  I've dubbed it; Dodgeball with guns.

It's a very simple concept.  Knock your opponent off, or instantly vaporize them.  KO's are worth more points.  Augment weapons with powerups.  Shoot the floor out from under your opponents.

Here is a small gameplay demo;