This applet allows you to play Los Alamos Chess against yourself.
This was probably the first chess variant, ever implemented on a computer.
The applet checks legality of moves according to the variant, except that promotion is only to queen. (There is no castling and pawns never move more than one square.) Rightclick on the image to go back to the original setup.
The applet was made by Hans Bodlaender, as part of his (hobby) `chess-applets project', version 0.03. Email me if you want the source code.