“You have to keep a dozen of your favorite problems constantly present in your mind, although by and large they will lay in a dormant state. Every time you hear a new trick or a new result, test it against each of your twelve problems to see whether it helps. Every once in a while there will be a hit, and people will say, ‘How did he do it? He must be a genius!” ~ Richard Feynman

This is a sometimes-updated list of my dozen (or so) top-of-mind frameworks for thinking about problems: