Maker Techmeology used a 3D printing pen to make a 3D printed centrifuge. Aside from the 3D printing, other parts used in the pen were completely recycled, with the motor being taken from a used appliance. Once completely assembled (for basically around a dollar), you’ll want to test the centrifuge and measure it for acceleration. While centrifuges can be used for any number of things, this one was originally created for spinning sample test tubes. Check out more details at 3DPrint.com: http://3dprint.com/100053/centrifuge-3d-printing-pen/