The Humble Bundle folks are giving away free keys DiRT: Showdown you can unlock on Steam during their continued Winter Sale.

"Race, crash and hoon your way through a world tour of motorised mayhem in DiRT Showdown! Crowd atmosphere, social gameplay and accessibility are all ramped up in this turbo- injected shot of driving delirium. Smash down the accelerator and earn the adulation of frenzied crowds at hyper-energised events at iconic locations. Trick, speed and smash your way to victory, then do it again."

Get DiRT: Showdown on Steam for PC, Mac and Linux by heading over to Humble below: