19 years ago
A chap was showing a new microscopic I/C engine a 1/4 the
size of a penny. He said that they were nearly at the point where
a wristwatch could be powered by lighter fluid.
I missed his name but a Google search on microscopic engines
brought out quite a bit on the subject.
see one is a wankel engine but the one on R&J was a single cylinder
Sounds easier to carry than a Lister L.