http://freetype.sourceforge.net/autohinting/index.html

Do these help?

As for comparison with CT, there is subpixel rendering: here's the font settings window on my Ubuntu box:

Is that kinda the direction in which you're asking?

I have some screenshots at home that I can post comparing Freetype, Cleartype, Greyscale and Quartz rendering of some fonts I've been working on. I'm not home until later this evening, so I'll check back then.

Also, Typekit has screenshots of different browsers on different OS's for each font. The browsers all add their own flavor, but if you know which is which renderer (see this forum somewhere) it may give you a general idea ...