This is apparently floating around on MacFixit, although I couldn't find it there in the forums or on the main page. The following hack will disable the anti-aliasing effect in some applications. I'm not sure which apps, as I haven't tried this myself yet (I actually like the anti-aliasing).
If you'd like to experiment, here's what you need to do.
QDTEXT_ANTIALIASING=0;QD_MINSIZE=18From the terminal, vi ~/.OpenStep/environment and then type the above line. Save the changes and quit. I'm guessing that QD_MINSIZE is the size below which the anti-aliasing is disabled.
Mac OS X Hints
http://hints.macworld.com/article.php?story=2001033121110769