If you're interested in some really great themes, you'll be glad to know that macthemes.net is back up and running! There isn't a ton of new stuff as it's been offline for a while, but it should prove to be a good place to find a lot of interesting themes and icons you often won't see released in Cydia: MacThemes Forum • Index page
Not sure if they're taking new registrations yet, but even if you're not a member you should be able to browse the forums.
Not sure if they're taking new registrations yet, but even if you're not a member you should be able to browse the forums.