Droid Cleanup

[TandemUser]

I've had my Droid since December and love it. However, with all the downloads and installs, I've noticed that my available space is getting low. I've moved what I can to SD, but I see a lot of stuff on my main system drive. I'd like to clean house and remove stuff I don't need, but am not entirely sure of what I can exactly delete (or rather, what I CAN'T delete).

Anyone out there have a list of required files or something, to help guide me in my cleanup?