Reading Artificial Intelligence: A Modern Approach (optional text book for http://ai-class.com/ ) to make sure I really understand A* before implementing it for http://aichallenge.org/
Three observations:
1 - The video lectures were a much better introduction to the material than the book alone.
2 - Having a "real" use case and implementing as you learn is a fantastic way to make sure I actually learn the material thoroughly
3 - I can't believe I went this long without learning this material.