Any Great Boxing Drills

I am getting into boxing now, i am wondering if any body has some good drills for me. I only have a heavy bag so, i might be getting a speed bag set right away... anyone have any drills?

Check out my other post here. Its actually a whole bunch of muay thai combinations(punches, and elbows, no kicks/knees.) So you can just go through there and practice without the elbows, or with them. Either way check em out and try them out on the heavy bag.