One of the things I wanted to do with the Do Interesting book was to collect examples of 'useful tricks people know or notice because of the jobs they do'. (The French have a term for it, sort of: "déformation professionnelle")
It didn't really work. I couldn't find enough.
But here's a great one from Dan: how to tell when your art is bad. (Print art, specifically, but probably useful for lots of things)