Sam Loman [just-sam.com] created an original take on illustrating the inner structure and workings of the human body as the tight intertwining of different systems (e.g. arterial, digestive, musculetal, respiratory, etc.), by way of a subway map metaphor.
The full size version is available below (by courtesy of Vizworld).
See also Animals on the Underground, Subway Map Bathroom Tiling, Redesigned NY Subway Map, Subway-Style Trend Maps, and Time-Based Subway Map.
Thnkx Peter!