Imagine swallowing a tiny robot that attaches itself to your intestines and starts walking about, all the while streaming back video to a watchful medical staff. That scenario describes what Carnegie Mellon University's Robotic Pill can do, and it just might be in your future if you have any kind of applicable problems.
The device starts its minuscule but epic journey with the patient swallowing it as a pill, then on the trip down it attaches itself to the intestine walls. The bot then extends it legs, and it starts walking about under a doctor's control. The device feet utilize tiny patterned arrays, allowing it to stick like adhesive without needing mechanical hooks or other means that could be more invasive.
The thought of having a small robot crawling around inside of them may turn a lot of people off from the ideal, but in actuality it could be a very effective tool for a non-invasive diagnosis (and could certainly beat the alternative). Of course, the device would have a very limited lifetime, so there should be no fear of having this thing active inside of you for any extended period of time, and when it has done its job it will be removed from the body in the natural way (if you get my meaning).
It is not hard to imagine a future version of the pill bot incorporating tools in its design, which would allow the doctor to actually do some intestinal work during the procedure. Of course, we can hope that such a bot does not turn on its makers and start attacking the victim from within – so it should be safe, at least until Skynet comes on line.