Steam, where it's on sale for $15 through February 6.
Antichamber, as crisp and busy as it may seem on the screen, might be more of a mental state than a game. As designer Alexander Bruce describes it, Antichamber is a "psychological exploration game where nothing can be taken for granted." It's like the experimental novel House of Leaves had a baby with Technicolor, then shoved it inside a PC. Or maybe it isn't – find out for yourself.