Many years ago SA ran an article by a cultural anthropologist who studied the flow of money in one of our poor neighborhoods (L.A., I think). He found to his surprise that there was as much money circulating in the poor neighborhood as in a typical lower middle class neighborhood, but in a different pattern. In the poor neighborhood, people were more impulsive; for example, hocking their TV’s etc for cash, then redeeming them when they got paid. A howling mob of commenters, as with Lomborg, set upon him for “blaming the poor”. So another helpful insight is obliterated by political correctness.

One of the neatest Amateur Scientist pieces I remember was how to use an operational amplifier circuit to regulate the pendulum of a clock. I never built it, but it’s still on my to-do list (if I can find the article on the intertubes).