'Nanotechnology', or engineering on the scale of a few millionths of a millimetre, is heralded as the field from which will spring the next generation of electronic components for ultra-fast computers, advances in medical technology, and miniature machines that can build smaller versions of themselves.
The prefix nano is derived from the Greek word for dwarf, and the minuscule objects on show have dimensions as small as those of the internal machinery of biological cells.
Some of the wilder speculation over the potential for this new field talks of machines small enough to slip inside the body. Tiny Rotovator-like devices injected into the bloodstream could scrape away at the furred-up lining of an artery, nanoenthusiasts claim.
This sort of application is years away, but consumer goods are starting to appear that include items made with the precision of nanoengineering. Examples include the tiny accelerometers inside airbags in cars, the holes inside bubble jet printers and pinhead-sized components inside video players.
Pinheads are common currency to nanotechnologists, who have modified the latest microscope technologies to etch all the words in the Encyclopaedia Britannica on to the head of a pin. They have also produced images showing individual atoms, and created new objects from scratch, atom-by-atom.
The Science Museum's new collection includes a tiny copy of the first Toyota car, less than 5 millimetres long, containing a working electric motor.
The advent of nanoengineering was foretold by the Nobel prize-winning physicist Richard Feynman in 1959. In a famous lecture, 'Plenty of Room at the Bottom', Professor Feynman offered two challenges, each with a dollars 1,000 prize. One was for the first microscope-readable book page shrunk 25,000 times. The other was for the first fully operational motor no bigger than a 1 64 in cube. The first took 25 years to fulfil, when a student at Stanford University in California shrank the first page of A Tale of Two Cities on to silicon. William McLellan, a 68-year- old engineer, rose to the second challenge in just over six months. Mr McLellan opened the exhibition in London yesterday.
He recalled his meeting with Professor Feynman, who had been inundated with crackpots bringing him motors the size of their fists. When he saw Mr McLellan clutching a microscope, the professor muttered 'uh-oh'.
Professor Feynman did not get the new technology he sought. The motor used existing engineering skills, though it represented the limits of old-style technology.
Progress now could be slowed down by tiny impurities clogging up the works of the small machines, Mr McLellan warned. 'There is certainly plenty of room at the bottom, but there's also plenty of dust and lint and dandruff too,' he said.