F.E.A.R. multiplayer has been released for free – you can go to the official site, sign up, download, and play. It’s a decent fps engine with really good graphics. I liked the single player a lot. It had issues but its core mechanics were really solid. The main downside is it will make even ninja machines cry, but since it’s free you’ve got nothing to lose – download it and give it a shot. Win32 only, sorry mac fans.