If you haven't tried this game yet and you like fast FPS, then I recommend you to do it! :) (The good old feeling that you got from games like Quake 2-3)
https://account.hirezstudios.com/tr.....campaign=email
And if I can get like 10 referrals, I can get a little bonus. ^^

This is an awesome FPS and it's even better as it's free! Yea yea.. still in beta and all, but who cares when it's awesome and free, right?