Security that is small and imperfectly formed  A nanotechnology
experiment that went wrong could lead to the ultimate weapon in
the fight against the forgers  Professor Russell Cowburn
normally views small things through a powerful electron
microscope. But as professor of nanotechnology at Imperial
College London, he's come up with a big idea for winning the war
against counterfeits. No matter how clever security technologies
such as holograms, metal strips or special inks become,
criminals soon bypass them.  "There is an arms race. People
introduce new technologies and somewhere between six weeks and
six months later, they've been cracked," says Cowburn.  Laser
surface authentication is now joining the battle and, if
Cowburn's dream comes true, may be the ultimate weapon for the
security marking industry.  The idea relies on a problem in
nano-technology: it's very hard to make exactly the same thing
twice at the nano scale. He was originally using microchips and
scanning their unique patterns with a laser wh