Bloxorz is a 3-D puzzle game in which the objective is to fit a rectangle into a square shaped hole by moving a block in the right way and in doing so the next level is unlocked. Here is a gameplay video Here is a link for the game. bloxorz.org.uk and sidenote: there is a bloxorz 2 but I haven't tried it so I'm only 95% sure its been released.