UPDATE: I have made a customizable version of this thing: http://www.thingiverse.com/thing:73634 Enjoy! I improved tolerances and parameterized the OpenSCAD of the derived project. Parameters: Number of rings, thickness of rings, ring width, spacing between rings, pin radius, center hole size. Now the pins are printed resting on the hole of the next ring providing natural support and better shaped pins. To allow this and keep the pins centered, each ring is slightly thicker than the previous.No support or rafts necessary. Printed with 10% fill and 2 shells with a .27mm layer height.My first thing!The print can be a little stiff initially but after sufficient playing the joints loosen up. If you print 6+ rings and do not want the rings to pop off I suggest you adjust the ring width to 6+.UPDATE: I just updated the .scad to allow the center hole size to be adjusted. UPDATE: I have added a .scad for a desk stand