I want to get into a little machining and welding.
Unfortunately I have a smallish townhome that doesn't leave me much room for a workshop, and even if I had the space, I'd probably have to go in to the tune of a few hundred if not thousands of dollars worth of machines, tooling, equipment, and materials pretty quickly, and I have other things to blow my money on.
I generally just like working with my hands, making things, figuring out problems, etc. and having some machining projects to figure out seems like a good way to fill in the gaps left by a pretty shitty math curriculum in my high school (I've probably learned more trig from watching some machining videos and only half paying attention than I did taking an actual trig class)