The Lucky 7 incident with Janice from ~1997 made me think about stuff damaged during shows. I'm not talking about mechanical/electronic issues and I'm not talking about regular wear-and-tear.
* The UK Wheel of Fortune had someone damage their wheel by moving it counter-clockwise. Video is out there.
* The Magic Toaster twice.
* On Win, Lose, or Draw (99% sure it was the Convy version), someone tested a marker by drawing some lines on the easel instead of on the pad of paper. The ink marks were visible for weeks.
* And the final episode of Rhyme and Reason, supposedly.