http://www.instantaction.com/ may have what you need. currently has free games. The two that I play most often remind me of Tribes 1 and Starsiege(Mech). I don't think they have much on arena style but that's sure to change and they are constantly adding new games. I am a hardcore gamer and a flex developer and I am just shocked by this site. Basically all the games you play are fully 3d rendered games in a actually browser window, no install or launch required.

I can't wait till the new .DocA$$ format comes out and my office 2007 cant open it unless I pay hourly :)

nice ending, the point was to make everyone scared that something bad was going to happen and then just to show you that everything back to normal an fine like the beginning of the show