ChipWits was a graphical programming "game" sold for the early Macintosh computers (and later to the Commodore 64).  It presented a tile-based programming model to instruct a simple graphical robot on how to navigate mazes, finding resources and avoiding enemies.  Although marketed as a game, ChipWits was a better tool for teaching programming concepts to non-programmersthan it was a game.
See http://www.chipwits.com/ for a modern version that's reasonably close to the original and http://en.wikipedia.org/wiki/ChipWits for a more comprehensive description and links.