National Physical Laboratory

An open day at the National Physical Laboratory in Teddington a few weeks ago revealed:

Holograms of watches and medals, that looked real.
Magic eye pictures (I can still see them!)
A microwave anechoic chamber. (I tried to speak, but sounded weird.)
A small door with a name plaque, "Bilbo Baggins".
Liquid nitrogen ice-cream.
Biometric recognition.
Precise measuring tools.
A large acoustic test tank.
Man made noses.
Old computers.
Alan Turing's personnel record.

And my favourite thing: holographic diffraction grating glasses, which make you see rainbows.