Micro Tetris
Jeroen writes "Students from the Vrije Universiteit Amsterdam used a so-called 'optical trap' to construct a version of Tetris that measures 25 x 20 micrometers. Blocks are constructed from tiny glass beads and all the action takes place in a waterdrop under a microscope. Considering the equipment needed, this must not only be the smallest, but also the most expensive Tetris clone around. A short description and a movie can be found here."
I'm sure this is one of those discoveries where someone said "Oh, neat!" and 6 months/1 year from now we'll have cured cancer based on it. But I can't help but think, right now, "Why?"
--trb