The best I have found is the plain old "Miracle Cloth", which is a sort of polish-impregnated yellow cloth that they sell in the cleaning products aisles at some grocery and hardware stores.
The cloth is covered with a waxy-looking product, it will shine and polish just about anything. Does a great job on brass, knife blades, and is great for removing rust from stuff. You just rub it gently on the spots, and it will take the rust off. Light rubbing for a longer period seems to work better than great pressure and elbow grease. The cloth leaves a light coating of waxy stuff on the metal, a couple of swipes with a paper towel and you have a great clean polish.
I was pointed to the "Miracle Cloth" after my Damascus blade rusted, the cloth took the rust off PDQ and polished the blade to an outstanding sheen. The tarnish it removes will turn the cloth black, but this doesn't interfere with its use.
Interesting side benefit - the coating it leaves behind seems to inhibit tarnishing, I used it for the brass frame on a percussion pistol and months later it still shines like gold when before it would start turning dull within a few weeks.