I did not want a trinket machine. Bought one to add to be used as a tool as I do a lot of carpentry and other maker-type stuff on the side. I feel like it's been a game-changer for me.
- Nearly completed the patent process on a technology to help guitar-makers using a system of plates and plugs that my partner and I designed and printed.
- I'll print scale models of whatever cabinet layouts I'm building. So much better than just a CAD model. The visceral effect of being able to see and hold a physical model is awesome and helps hone in on a final design better.
- Countless jigs, fittings, gauges, and guides.
- Tons of things that I could buy, but are much cheaper and often faster to print - Example - Zero Clearance Table Saw inserts run about $50/pop.
- Some things that I could buy, but don't quite fit what I'm doing - ie "generic" dust collection fittings vs custom ones with the angle I need.
- All types of organizational inserts, trays, and parts.
Almost all of the above were done in Fusion 360. I never used 3D CAD before buying my printer, but I've found it easy to learn and there are a lot of resources. Of course, there are huge libraries of things you can find online and print without any CAD know-how - I'll echo Fatzilla's comments about about finding things that break. Any of these you're interested in seeing, just ask.
I'll also agree with OldArmy07 above, the Prusa printer just works. I've got a MK3S+ and I'm considering adding a MK4. I think today Bambu probably has Prusa beat on paper, but I've been so happy with the quality and ease-of-use, I'll keep supporting Prusa. Nothing against the Bambu, though. They are pushing the market forward.