I have written a demonstration of a simple path-finding algorithm (in Python), for use in grid-based computer games. It used a breadth-first search to route a sprite from one part of a map to another, avoiding obstacles in between. The code is a listing taken from my forthcoming book, Beginning Game Development with Python and Pygame. There's no documentation I'm afraid. If you want to know how it works, you will have to buy the book. :-)

To run it, you will need PyGame, and of course Python. The code is completely public domain, use it for whatever purpose you want and you don't owe me a penny. Here be a screenshot...