A small DC motor (available online for ~$3), a USB cable (any old one you have lying around), a fan blade (you can salvage ...

Not long after Dyson unveiled their “bladeless” fan, a fairly steady stream ... essentially every piece of this project has been printed on a standard desktop 3D printer.

However, he had to make a modification to enable proper thermal management, as these cards were not designed to be used in regular desktop ... by 3D printing a mount that carries three fans ...