Right now, an atomic clock works by sending atoms through a vacuum, microwaving them and measuring how many waves it takes to maximize atom florescence (that's 9,192,631,770 microwaves or one second).
Needless to say, this testing requires a lot of bulky equipment that's at least a cubic meter in size.
Now, a team of researchers out of Reno have successfully used a new technique that cuts down on gear. Using lasers (of course), scientists can hold atoms to be observed in place without a vacuum. The system still requires a bit of equipment, but it could pave the way for portable atomic clocks to be used in space laboratories, or just very, very complicated watches from Tokyoflash. [NewScientist and image]