Artifact — Equipment, 4 (4)
Uncommon
Equipped creature gets +4/+2.
Equip—Sacrifice a creature.
It comes off as easily as your own skin.
Illus. Jason Felix

9/22/2011: You can sacrifice the creature Demonmail Hauberk is equipping in order to equip it to another creature.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Extended (Type 1.X)
Legal in Standard (Type 2)
Legal in Classic (MTGO)
Legal in Commander
Legal in Modern