puzzles Google Puzzle Party – complete jigsaw puzzles with your friends, wherever they are Mark Frauenfelder
Games How the mystery man from a forgotten Alternate Reality Game was found 15 years later Rob Beschizza
useful stuff Excellent cheap puzzle book: The Moscow Puzzles: 359 Mathematical Recreations Mark Frauenfelder
puzzles "Blocks" is a fun web-based puzzle game that gets increasingly more challenging Mark Frauenfelder