Paradox Interactive gave away Steam keys for EUIII: Chronicles (that's EUIII Complete and the expansions Divine Wind and Heir to the Throne) to all their forum members as a way to celebrate reaching 500,000 members. I saw a few people on the forums here playing Crusader Kings II before, so I figured there must some grand strategy fans here. Might want to check out some Let's Plays if you're unfamiliar with the game. I've already got it, so if you're interested grab one of these keys:

36NZV-B52R5-B9RRA

Y46CI-7DF6P-5WTIX

Just go to Add A Game on the bottom left of Steam, then Activate a Product on Steam, input the code and you're good to go. Enjoy your quest for world domination.