I recently read about Chernoff faces
(http://en.wikipedia.org/wiki/Chernoff_face) in one of Edward Tufte's
books (great read btw) and would like to mess around with them in
matplotlib. My current approach is to generate the faces as images,
and then use them as markers on an x-y plot (like the example I
found in the Tufte book). I just realized, though, that I have no idea how to
incorporate images as position markers in matplotlib, or if it's even
possible. My search of the mpl docs didn't turn up much.