Kugelbahn is the german word for Rolling ball sculpture.
When I first toyed with the Pippy Physics code, this immediately
came to my mind: create a small toolkit to construct a structure
and populate it with little balls that roll along.
Sound seems to be very important!
Later on I discovered the Physics Activity. This is very close
to what I have in mind. I am pondering the idea to make
a specialisation of this Activity to more closely mimic a
real construction kit.