Looks like the president of Gearbox Randy Pitchford is giving away SHIFT codes for golden keys at various times this weekend.
https://twitter.com/DuvalMagic
These are currently good for 1 activation per account for the next 2 hours.
Win PC: C3WBT-6BZF9-FBJBJ-B3JJJ-BB53S
X360: K3K3T-H6B5F-J6FBX-563J3-BSHZX
PS3: K3K3T-H6B9B-R9BCT-935J3-BSHS6
enjoy
PS. if you don't know what shift is, click extras in your Borderlands 2 Main menu.