I've been using the Dark Red v3.3 by Rellims for a few weeks. Super clean, looks great, works great, and doesn't eat memory. I also like Blue Goo. Really cool custom theme, and it too works great. Both are free.
I also have Mothy's Storm 3D Hidden Today Weatherbug Edition. Not free, but cheap and very nice looking.
Think I'll check out the BBOS theme though. Looks very nice!
Themes: miro 2.0, Earl Grey
3rd Party Apps: Weatherberry, QuickLaunch, Google Maps, AmAze GPS, Trapster, Meterberry, Opera Mini 5, Facebook, App World, Speedtest, Level, ScoreMobile BB, Pandora, iheartradio