Right now, Battlefield 3 is only $5 via Origin (Close enough to free
). You can go
here to download Origin if you don't have it. Once you do buy BF3 from the store for just $5! You can also get the exciting DLC 'Close Quarters' for free! (Real free this time :3). To get it just click the 'Origin' in the very top left, and click 'redeem code'. The code for Close Quarters is "BF3E3". Enjoy playing with me, Koolio, and soon yourself! (Lol playing with yourself ._.).
Note: BF3 by itself takes up 10GB and Close Quarters another 3-4GB. You also need a good-ish computer to handle the game. Check
here.