I've had this happen a couple of times now. There's definitely some jobs where I looked around and realized I'd used just about every tool I have.
I think the only disappointment at the moment is my Makita rotary drywall cutter - a reciprocating multi tool is just so much easier to control and makes nice straight cuts easily.
Still waiting for the welder to have its moment though.
Those rotary drywall cutters are the ticket for cutting plastic. I first used one when I was a mechanic before changing careers, and we used one for trimming tough plastics like bumper covers. Takes a bit of practice to get a nice cut, since they are super aggressive, but they make a very nice, clean cut that's far better than any other tool I've tried. I've actually never used mine on drywall, I prefer one of the oscillating tools or a jab saw, but I've used it quite a bit for automotive and electronics work. You can make a front panel for a project stupidly quick with one of those, and it turns out nicer than cutting with a dremel cutoff blade.
