I build all sorts of things for all sorts of things.!!
I use them to make covers, limit switch brackets, terminal boxes, Motor covers, etc and even Motor mounts on some machines I've built. They are great for proto typing parts for checking fit and looks etc.

I build jigs using them and all sorts of things little things that you wouldn't other wise bother making because not simple. Provided your handy with Cad then it's simple with 3D printer, just hit the go button and walk away, several hours later you have ready made parts.