Late to the party here...
A couple years ago I bought a little Craftsman buffer on clearance for about $100. I think that was half-price. I've used it on all my pipes since then. Before that, I had put a small buffing wheel in my drill press. It worked okay, but the small wheel was difficult to get into corners, and I had a tendency to touch the pipe to the spinning chuck, inevitably scratching it. For that reason, I really don't recommend anything chucked into a regular drill.
The Dremmel tools do have buffing wheels available, and that's not a bad way to go. But again, the small wheels can make it difficult to get into corners.
As has been said, if you want to do some tinkering, you can set up an electric motor (washing machine motor, vacuum cleaner motor, etc.) and rig up a wheel on the arbor. You may have to use bushings to get the arbor to the right size, for example. Get some felt wheels with loose felt, some buffing compound, and off you go.
More important than your exact setup is your technique. When buffing on a stationary tool, hold the pipe below the bottom half of the wheel, not on top of it. You should be lifting the pipe into the wheel, not pushing it down into the wheel. Use two hands at all times, and hold on TIGHT. I've had a buffer throw a pipe across the room and break it in half before. Use a light touch, and keep the pipe moving. (You can put a burn mark on a stem in short order, especially with a high-speed buffer.) Be especially careful around delicate edges, such as the edges on square shanks as well as the button. You will find out with practice how often you have to re-charge the wheel with compound, but I find myself recharging once with each pipe, more or less. Practice will teach you a lot. Good luck!
