I keep wanting to refer to this short story when discussing the movie Avatar with friends, but I can't remember the name or who wrote it.
In the story, a researcher projects his consciousness into the body of an artificial ant. The ant body was metal, and it was, to the ants being studied, completely indestructible. The ants learned to lure the researcher into tunnels and then collapse them, burying the artificial ant.
Over time, the researcher began to identify more with the ants than his colleagues. They began to worry that he was spending too much time projecting his consciousness, and he seriously creeped out a woman (a fellow researcher?) with his increasingly antlike behavior.
By the end of the story, the character had alienated many (most?) of those around him.