The listing, Borderlands [Steam Key] has ended.
http://store.steampowered.com/app/8980/Borderlands/
Lock, Load, & Face the Madness
Get ready for the mind blowing insanity! Play as one of four trigger-happy mercenaries and take out everything that stands in your way!
With its addictive action, frantic first-person shooter combat, massive arsenal of weaponry, RPG elements and four-player co-op*, Borderlands is a breakthrough experience that challenges all the conventions of modern shooters. Borderlands places you in the role of a mercenary on the lawless and desolate planet of Pandora, hell-bent on finding a legendary stockpile of powerful alien technology known as The Vault.