Seems I forgot to post this in the silliness.
World of Goo for
whatever you damn well want to pay. Up there with Portal as one of the best puzzle games in recent years.
There's a PC, Mac and Linux version, offer's on until the 19th, demo is also at the link, be nice!
Utterly charming stuff.
From one of the best puzzle games of recent years to one of the best games period,
Civilization IV: Complete Edition is on sale on steam - not free but 50% off.
Contains Sid Meier's Civilization IV, Civilization IV: Warlords, Civilization IV: Beyond the Sword and Sid Meier's Civilization IV: Colonization.