[Tim Good] built a 3-axis gimbal out of 3D-printed and machined pieces, and the resulting design is pretty sweet, with a nice black-on-black look. He machined the flat pieces because they were too long to be printed in his 3D-printer.
The various axes swivel on four bearings each, and each ring features a manual locking mechanism made out of steel stainless pins that immobilize each axis. The gimbal operation itself appears to be manual. That said, [Tim] used 12-wire slip rings to power whatever camera gets mounted on it–it looks like the central enclosure could hold a camera the size of a GoPro