At A Distance is a co-op puzzle game from Terry Cavanagh, creator of wonderful indie platformer VVVVVV. It's designed to be played by two people on separate, nearby PCs. Each player must wander through a fuzzy environment, messing with everything they come across. Actions in one world will affect the other, and it's up to the players to figure out exactly how through experimentation and shouting. Once the relationship between worlds has been discovered, you and your partner must work together to solve the grand puzzle.
Shacknews reports that the game is now free for everyone. You can download it now from the At A Distance site , where you'll also find instructions on how to get it working. Good luck! Let us know how you get on.