Which lenses do you guys use the most. I'm getting ready to buy the adapter, but I'll need some lenses. I own a Nikon 50mm for my D300. What others would you guys suggest?

Any lens with a low aperture number will work fine. As long as it fits on your mount! If you have an adapter with a Canon FD mount, for instance, then your lens must be compatible with an FD mount. But I think you already knew that! :P

Personally I have a Pentax DSLR and two lenses that I use. Inexpensive ones, but for me their the best! Pentax 18-55mm kit lens and a Tamron 70-300mm f/4.5-5.6 lens. I'm also planning to build a 35mm adapter for my camcorder, in which case I'll use an old lens of my Dad's that has an aperture of f/1.8 and is 50mm. That way I'll get the great shallow depth of field that everybody loves!