Now, everthing REALLY works on Paper!

Meditating on the fabulous Rob Ives gizmos ...

If this automaton is not the Symbol of Inventors, always trying the Impossible, I don't know what is ...

Die Fledermaus , the flying mouse. Turn the handle and the fiendish blend of slider crank and cam make the bad flap his arms frantically in a vain attempt to fly. He's batty to even try!
As the handle is turned, the mouse makes one pass for each turn of the handle while the arms flap four times! Print this model onto thin photocopier card then all you need made ​​to the model are scissors, ruler,
PVA glue and a sharp knife.
And it occurred to me now, everything can really work on paper, not in the old sense, that, in theory, everything works, but in the sense that a lot of machines can be produced in a "sketch", a simplified, Paper, or Card-stock.

This becomes even more useful, with the traditional Notebook, which should always accompany a Gizmo Maker: 

Add small scissors, glue and an a small X-acto style knife, those of Key-rings, and you may well test a new idea, and demonstrate those you already had, live, and direct, to potential investors!

So, when they say, "will that REALLY work?", grab a piece of paper...
And demonstrate!