Ubisoft's real-time strategy World in Conflict is free on PC for a limited time. The Complete Edition includes the Soviet Assault Expansion Pack, as well.
To get the game, click on the link below and log into your Uplay account then you can start downloading through Ubisoft's Uplay client. Once you get the game, it will be yours forever.
The offer starts on December 4. at 2 pm and runs until 10 am on December 11.