In this age of digital bloat, you might be surprised to hear that making a game as small as possible is an attractive challenge. But this tiny implementation of chess is just that — and takes up just 487 bytes on your hard drive.
BootChess was released this month. It trumps the previous smallest chess game — 1K ZX Chess — which held the record for 33 years with its rather extravagant demand for 1024 bytes of storage. As you'd expect, you can forget any graphical interface: instead, pieces are represented by ASCII characters (capitals and lower case represent white and black) and moves are made using the usual chess square notation.
You can download the game; it will run on Windows, Linux, OS X, DOS and more. It perhaps wouldn't challenge any Grand Master, but if you're not much of chess player it may still make you sweat. [BootChess]