ShotCode
From Just Solve the File Format Problem
ShotCode is a 2-D bar code symbology created in 1999 at the University of Cambridge. It consists of a dartboard-shaped pattern with a bullseye in the center; the code is read based on the position of parts of the shape relative to the bullseye. It was used for product promotions, but doesn't seem to be very active since about 2007, probably because other code systems such as the QR code have dominated for such uses.
