An outrageously encyclopedic mathematical analysis of hundreds of classic games and puzzles, like Rubik's Cube, Hex, and Dots and Boxes. The Art of Computer Game Design . Out of print. Originally published by McGraw Hill, 1984. Lays a conceptual foundation for thinking about computer game design issues.
Examples are old, but the concepts are still valuable.
From the game designer who started the Game Developers Conference. The Art of Puzzle Design . From Physical to Computer . Advanced Lingo for Games . If you want to program games for the web, start here.