Simplicity is beauty:
I first discovered the Candido theme engine when I stumbled upon the excellent (and quite elusive) Carbon theme included with Linux Mint 7. Sorry, no link provided, as there’s not even an author name in the gtkrc file—which is a shame, because I’d love to thank the theme’s creator for whipping up such beautiful eye candy. My only complaint is that the default tooltips are an ugly gray. However, after browsing the web for several hours, I managed to find a solution. The overall results of using GNOME + Candido + Carbon + the gnome-colors icons have been enough to keep me salivating over my desktop (instead of working) for the last week.
GNOME users in search of a quick and clean interface: Candido is teh shiat.