Here's a mobile we recently sent off to a private residence in California:
It's based on a mobile we made for the HGTV's Divine Design (See April 24, 2008), but includes a mix of copper, brass, and stainless-steel shapes. The bottoms of the shapes are bushed, and the tops are polished so the varying colors will reflect nicely on the ceilings. (And don't worry, the client's ceilings will be much prettier than our shop ceilings!) The entire mobile hangs 20" wide by 60" tall.