My 11 year old microwave died and I salvaged the ring and glass tray from it and made a spice holder, using clear caulk to hold the ring in place. I placed the glass tray upside down on top of the ring, drew a 'template' of where the clear caulk needed to go, let it dry overnight, and it worked for holding the ring/tray in place.
So good to recycle. Great idea!
