Let me just say that one more time: laser-powered carbon nanotube exploding drug grenades. We have them.
A drug grenade is exactly what you think it is: something that explodes and releases drugs into your body. Since swallowing a lit fuse doesn't usually work that well (not to mention the horrid aftertaste), researchers have been looking for other ways to perform targeted drug delivery, and laser-activated grenades made of carbon nanotubes just might be the answer.
Since carbon nanotubes are tubes, it's fairly easy to fill them with things, and researchers from the University of Rochester have suggested that it would be possible to mix drugs with water and seal them up inside nanotubes to make little druggy pipe-bombs. To set them off, you'd heat the nanotube capsule with an infrared laser, causing the water to instantly boil. The huge increase in pressure from the boiling water would bust the nanotube open, releasing the drugs stored inside.
The clever part to this idea is that you could take these drug-laced grenades by the fistful, but they'd only go off where the infrared laser was targeted, making it possible to deliver drugs just exactly where and when you wanted them and nowhere else.
This is all just in simulation so far, and as you might imagine, there are still a few potential kinks to be worked out with this technology. Say, for example, determining whether setting off a bunch of nanogrenades inside your body might, you know, damage some stuff that would be better off not being damaged. If it works out, however, it could offer new ways to treat all kinds of things, with a precision that's never been available before.