Hadn't had enough of really cheap games today? Good. Because DiRT 3 is free for the next day or so, and you should totally get it.
The offer is available for all of today and most of tomorrow courtesy of the Humble Store. It's a pretty simple process: add the game to your cart, login to your Humble Bundle account (make one if you don't already, since it makes buying bundles like this one easier) and check the game out. For free.
And bam! You have an exceptionally good arcade racer that also doubles as a fun multiplayer game. The Games for Windows Live nightmare has finally been patched out, thank God, which was the main reason why I'd deleted all the DiRT games off my hard drive previously.
Note that you've got just over a week to redeem your Steam key from when the "order" completes. But since you can add games to your account without downloading them, that shouldn't be too much of a problem.
So there you have it! Free DiRT. Which means you and your friends can start replaying that crazy zombies mode where one car is "infected" and everyone has to run away and "survive". It's reason enough to download the game, and if you don't believe me then watch. (Ignore the crappy music at the start.)