Pentopper

Bic pens are universal. Nearly 150 million of them are sold each year in the US alone. But what if you want to hang them next to a noticeboard? How often have you seen one of these pens with a piece of string wrapped untidily around it, secured by a mess of tape?

Well, no longer. It took me just 10 minutes to create this pen topper using Autodesk 123D Design, and a further 18 minutes to print it. And you can read how to design one yourself even if you have no knowledge of CAD design:

http://www.3dgeni.us/pen-topper/

A useful introduction to 123D Design.