Think "Nano Car" and Indian maker Tata's budget minicar might come to mind. A Smart ForTwo is pretty small too, and there were even smaller cars driving around Europe in the 1950s during fuel shortages.
None of them were quite
as small as a new "car" created by scientists at the University of Twente in the Netherlands, though.
According to the BBC
, the "car" is made up of a single molecule, made of just a handful of atoms. Four branches sprout from the ends and since they rotate when an electric current is applied, they can be considered wheels and the molecule itself an electric car, of sorts.
The tip of a scanning tunnelling microscope, which ends in a point only a few atoms across, supplied an electric charge in ten bursts. When electrons jump from the tip of the microscope to the molecule car the "wheels" change shape and rotate. All this is achieved in a vacuum and at -266 degrees celcius, or -446.8 Farenheit.
With a range of around six billionths
of a metre it makes most of today's electric cars look positively intergalactic, but since it's too small to sit in - or indeed see
without an incredibly powerful microscope - we suspect range anxiety isn't an issue.
Contrary to appearances it's not just about fun and games. The idea behind molecular machinary is to help develop future technology development in all sorts of fields.
Tibor Kudernac, a chemist at the university, points out that "In all biological systems are a vast number of molecular machines or rotors based on proteins that do important things very well; muscle contraction is based on protein motors"