Stirling Engine as a working model

Are you still wondering what to do for the holiday?

The Stirling Engine is a very different type of engine to the internal combustion engine - the petrol or diesel engine in most vehicles.

In a Stirling Engine the energy comes from outside and the gases that do the work are sealed inside.
This German site - the link is to a translated version of their catalogue - is selling a papercraft kit of a Stirling Engine that works using a hot cup of tea or coffee.

There's a nice little video of the model in action.

Wikipedia has a detailed article about the Stirling Engine for those who want to know more.