I came across this sketch today while cleaning out my desk. This is the Life Tube; I was attempting to imagine the tubular structure of a 4D human.
Each cross-section of the shape is a moment in time. The radial shape of the tube at any place along it's length is given by the position of the person at that moment in the timeline (timetube?)
The tube starts with birth, expands as we grow in size, and comes to a close as the lifetime ends. It kind of reminds me of those Hare Krishna info-book illustrations.
Have you ever thought of yourself as a time-tube? This kind of leads into the idea that we are essentially donuts. Consider the hollow tube from one end of the body to the other, and how we are symmetrically aligned around this hollow center.