Not only are Usus ballpoint pens with SupraSpin magnets quite lovely, they're a delightful example of applied technology. In this case the body is made of aluminum, but they also come in transparent polycarbonate that lets you see the action inside. Instead of springs and screw threads, the pens are completely controlled by tiny rare earth magnets. To write, twist, and a magnet pushes out the ballpoint tip. To change the cartridge (and the ...