Maybe dust collectors. I have five of them collecting dust in my basement. Two Kyosho 1/8 scale chain driven Vanning off road cars (one still in the box) and three Team Associated RC300 on road 1/8 scale cars with Lexan bodies.
Occasionally I notice their bumpers sticking out from underneath a bench and I wonder it all those motors are seized up with corrosion. I'm afraid to look.

I do most of my reading and posting in this 3D forum because all my 3D planes keep me busy these days.