Firefox renders much faster and smoother if you enable Direct2D drawing. It only works on Windows 7 or Vista SP2 with driver platform update. Tested this in FF 4.0b2 BTW.
http://forums.mozillazine.org/viewtopic.php?f=23&t=1775755
Contrary to what most people say, text looks much better with 16xAF forced in the control panel, at least on ATi 5xxx series cards. Without 16xAF text looks crappy no matter what cleartype and smoothing settings are set in about:config.
That's some real high quality text there. The edges are blended perfectly unlike the cleartype edges.
[qimg]http://a.imageshack.us/img841/6517/direct2d.png[/qimg]
Much better than the windows rendering. It might seem odd or uncomfortable at first after being used to the darker windows text, but shouldn't take more than 20 mins to adjust to it.