An ingestible, folding robot made partly out of sausage liner has been designed by researches at MIT, the University of Sheffield, and the Tokyo Institute of Technology. (I'm not doing an acronym for that one in English...)
The plan for the design is that somebody would swallow it, it would break out of an ice capsule, and deal with small foreign objects that are often swallowed accidentally, especially by children. Without the need for invasive surgery. Pretty neat.