The Simply Green blog recommends the GE's Energy Smart dimmable compact florescent bulb.

What I like about the bulb is that it mimics the light of a traditional bulb, all while giving you the huge energy-saving benefits of using it. It lasts 6 years and will save you $45 in energy cost savings over the life of the one bulb. I was surprised how soft the light was when I flipped the switch on the lamp. I found myself carrying the bulb going socket to socket around the house seeing how it worked in other fixtures.

At $11 a piece, thats a good price. I question how long it actually will last. I've had plenty of dimmable CFLs die in under a year. The cheaper they are, the less likely they will live up to their claims (unless the technology has actually improved).

I'm sticking with regular and halogens for now.