The Official Site of Major League Baseball
Because it appears to be a Flash application I don’t seem to be able to link to it directly, but the Gameday live action scoring of games at mlb.com is really great. Okay, maybe most of the features are similar, except at mlb.com they have a batters box that shows pitch location for each batter.
I can’t say I’ve made as much use of it as one might, but it definitely elevates the notion of following the game on your computer to see where each pitch was, and in what sequence.