Activate the Cold Ray!

In one of Sir Arthur C. Clarke's nostalgic essays about prewar science fiction he drops a little scorn on a story by S.P. Meek about a "cold ray." Clarke points out that you can't have a "beam of cold" because cold isn't a thing, it's an absence. So the whole idea is silly.

Unless it isn't. Behold laser refrigeration! It's not quite a "cold ray" but it does use lasers to make the target colder. The trick is that the target is a Ytterbium crystal and the lasers are exactly tuned to stimulate fluorescence by the crystals. The energy emitted is greater than the energy absorbed, making the crystals colder.

Now unless you happen to routinely wear Ytterbium clothes, you're not going to have to worry about Mr. Freeze zapping you with his cold ray, but it's still pretty awesome. Now excuse me while I fire up the laser to cool my drink.