As everybody knows, font AA sucks a lot

Especially the Apple sub-pixel rendering that seems to only works well on apple screens !
If you are using Tiger you can use the wonderful
Unsanity Silk. It lets you control font rendering by application, fonts can be substituted...
Unfortunately it does not work with Leopard anymore. So here is a hacky method to disable font AA in mac os. It used to work with all mac os x versions (10.x) :
defaults write .GlobalPreferences AppleAntiAliasingThreshold 200
The above code disables font AA for all fonts having a size less than 200 points (this value can be increased if needed). However, title bars and menus are still rendered with some anti aliasing