Like and enter the redemption code (SAVO2012) to the Dollar app at https://www.facebook.com/Deathrally/app_245405195585499
The app gives you a Steam product key, which can be activated by opening the Steam client and going to Games -> Activate a Product.
Finally go to the Death Rally product page at http://store.steampowered.com/app/108700/ and you’ll be able to purchase the game with a 90% discount.
Be quick to claim your code before they run out! The offer ends December 31st 2012.
Btw the coupon also expired at December 31st 2012.
Death Rally Store page
http://store.steampowered.com/app/108700/
TIPS: Using private browsing to get multiple times :D
Sweet!