A faster key repeat rate for Mac OS X

defaults write NSGlobalDomain KeyRepeat -int 1

The fastest one can get via System Preferences is 2. You can set it to either 0 or 1, depending on your preferences.

To check your current repeat rate, issue the following command in Terminal:

defaults read NSGlobalDomain KeyRepeat

See: http://hints.macworld.com/article.php?story=20090823193018149