Steam will begin offering ibb & obb in under two hours, though those interested in this co-op, gravity-defying puzzle/platformer have until June 2nd to take advantage of the game's 20% preorder discount (thanks [VG] Reagle). Here's word on how this will turn your world upside down: "ibb & obb is a two player cooperative game set in a puzzle filled world where gravity goes both up and down. You can only succeed by working closely together. Find a friend for some true local co-op couch fun or match up online."