A good implementation of the game Connect Four done in javascript with a more-than-competent computer AI player, implemented with a minimax algorithm. Unfortunately it only runs in Internet Explorer. It’s part of the WebFX site, which features all sorts of nifty DHTML and javascript toys and menus.

Playing the actual game against a real live opponent is decidedly more fun than being consistently (well, 75% of the time) beaten by the computer, though. One two three four, one two three four, one two three four, CONNECT FOUR! (damn, advertising really works doesn’t it)