Sam Lomen's Underskin charts a transit map to the human body. And no matter what the locals tell you, don't take the pink line to the yellow line. That's nowhere you want to go. [Behance via StreetAnatomy via TheDailyWhat]
"Next stop, Anus. Please stay clear of the doors and wait until the train has come to a complete stop. In the likely event that filtered oxygen is needed, a gasmask will be released from a compartment over your head, secure the gas mask over your nose and mouth. Please help yourself before helping others."