This news is about a week old now, but it's fascinating enough to share anyway. Scientists at something called the Wyss Institute for Biologically Inspired Engineering (which sounds like something from a Monty Python skit, but which is actually based at Harvard) have developed a killer robot made from DNA. How cool is that?
As explained in an article on Forbes.com, the robots are constructed from DNA, which makes them extremely small. Because of DNA's structure, it can be manipulated into shapes (like smiley faces -- really), in a process called "DNA Origami" (again -- really, I'm not making this up). In this case, the DNA is folded into small hinged barrels. The barrel is then filled with a chemical. The DNA can then be programmed to look for particular molecules, like cancer cells. Because, unlike some other nanotechnology particles, DNA is programmable, it can look not only for the particles, but also be set up so the molecule it finds can "unlock the barrel" and release the chemical.
The scientists tried it out on two cancer cells, filling the barrel with fragments of antibodies, which were then directed at cancer cells. The antibodies gave the cells instructions to kill themselves. (Which brings it all back to another Monty Python skit, it seems to me.)
Mashable.com also has an article about the DNA killer robots, along with a video.
Like so much cool nanotech, this is all still in the laboratory stages. They'll try it on mice at some point, and then start planning on how to test it on people. So, the day of reckoning with our eventual Killer Robot Overlords is a while off. But it's exciting to think about the possibilities, anyway.