Oxalic acid!!! someone linked to a BMX forum where a guy used oxalic acid, I tried it and all I have ot say is

OXALIC ACID!!!!!!

It's sold as wood bleach in hardware stores in a powdered form. You mix it in some with water (I'd say roughly 1/4 or less as strong as the instructions reccommend for bleaching wood) and simply soak the chrome (or whatever) that has the rust on it. Depending on how strongly you mixed it will determine how quickly it works, but basically you just need to kind of brush off the rusted area maybe once or twice while it soaks and after a while the rust is simply gone. I had two wheels, fenders, steel calipers, steel brake levers, handlebars and stem coated in rust, they soaked for a couple hours in a plastic tub and the rust is completely gone. It doesn't do anything about pitting of course, so the chrome now is completely shiny but textured in an odd way.

I will never scrub rust away again. There was virtually no labor involved. This was a complete bike I'm rebuilding to sell- every bit of chrome coated in rust- it's totally shiny now and I spent maybe an hour or two total dealing with it.

I'm telling ya' - Oxalic acid!