TurboSpinner
After publishing my MoneySpinner - http://www.thingiverse.com/thing:1937473 - I was searching for another way to provide a spinning mass that was small enough to stay within the dimensions of peoples' hands. I found a used bull nose ring from the days when we used to take cattle to agricultural shows.
The challenge here is to find a 'standard' size so that the STL files will fit in rings that are available globally. I have included to STLs, one that I know works with readily available Australian nose rings and one that Google tells me should fit with US (3 inch) nose rings.
For anyone who can access these nose rings and wants to print one for what they find, please provide me with the inner diameter of the ring and the thickness of the brass itself and I will try and amend and upload an STL that fits those measurements.