Facebook's Messenger is turning out to be a robust communications platform, boasting over 800 million users. Aside from staying connected with your friends and family, the messaging service has a hidden chess game that you can play from within a conversation window. All you need to do to get started is use the following command: @fbchess play.
It looks like the game has been available for at least a month now. The game is text-driven, which means that you're going to have to use algebraic chess notation. Here's a quick guide, as detailed by Facebook:
1. Start game with random colors: @fbchess play
- Pick the colors: @fbchess play white/black
- Pick the opponent: @fbchess play white John
- @fbchess e4 or @fbchess Pe4 moves pawn to e4
- Nbd2 to move knight from b-file to d2
- B2xc5 to take on c5 with 2nd rank bishop
- e8=Q to promote pawn to queen
- 0-0-0 or O-O to castle
4. Offer a draw in the current position: @fbchess draw offer
5. Offer an undo of the last move: @fbchess undo
6. Resign: @fbchess resign
Interested? Open up the Messenger app on your phone or head on over to messenger.com to get started.