What was your unexpectedly best 'MacGyver' fix for something?

Yellow duct tape for someone's saxophone. In college, my school's football team played the University of Michigan one year. The marching band got to take coach buses since it's like 2 hours away. After loading some instruments on one of the buses, the bus driver decided to move the bus with the storage doors open. Someone's sax got thrown onto the road. Crucial pieces fell off. I had yellow duct tape that was a very similar color to the lacquer finish on the sax so I duct taped the pieces back on. It actually worked!

Duct tape for a crack in my front bumper. The silver/grey even matches the color of the bumper. My mom has yet to notice it.

My original Xbox’s disc tray stopped ejecting. I tried prying it with all kinds of tools. Eventually, out of frustration, I pressed the eject button and slammed the top of the console. The disc tray came right out. Have no idea why this worked but it did, and it worked up until I stopped using it.

A baby gate when we first got our Yorkie to keep her from going upstairs and going after our cat. The way the stairs were built one side was a wall and the other side was a banister so the gate didn't fit the way it was supposed to along the banister side and the Yorkie would just push it up and go under it or jump until it tilted back and go over it.

Fix involved string and some bent metal coat hangers, duct tape to hold it all together nice and tight, and double sided tape to make it sticky and uncomfortable for her to try and push the gate. Worked until we had the electric fence checked out and cleared, since we'd had one for our previous dog but her death was some years prior and we weren't sure the fence still worked so we had to get the company to come out and make sure.