The weathered texture of these steel pendants is strangely touchable. Some are available with a gold finish as well as bronze, others have free-moving parts that highlight their topology. All are math, art or both.
Sale: I'm moving most of these designs to Shapeways, where you can get them in many more materials and finishes, from $6 plastic to $3000 platinum. So I'm offering my remaining stock of steel models at $25 apiece. (Except the tiny Klein bottle which is a whole different technology – those are $55 now, but they'll list for $140 after mine are gone.)