Rakion
 

Recently found this, and it's quite fun. It's a mix of RPG and FPS. Free to download and play (they make money through a cash store). It's annoying to go up against a cash (poweruser) user but they have a Basic Mode where everyone is equal. Plus skill is greater than greed, and lvl 1-11 games aren't bad. It's certainly fun for a week or two, give it a try.

http://rakion.softnyx.net/download/client.asp