So, I was listening to the Jacks in my garage while washing the car in the driveway (because why not while I have them!) and I went to move the electric pressure washer. What I didn't know is that the extension cord had gotten wrapped around the back side of the amp and mixer, and moving the pressure washer pulled on the cord and sent both crashing to the ground.

100% my fault. I went over to pick everything up and assess the damage and noticed only one Jack was working. After some troubleshooting, I found that one of the amp channels had quit.

Power cycling obviously did not work. I noticed some crackling through the Jack when I moved the amp, so I thought to myself, "Self, since a smack to the ground broke this thing, would a good smack fix it?" So I lifted that side of the amp up and dropped it from about 2-3 inches. *crackle crackle pop!* I did it again and POOF! Music start coming out of the Jack nice and clear. Working fine now, though I know something is probably loose inside. Good ol' percussive maintenance.
That got me thinking. I'm sure many of you have stories of using percussive maintenance to fix something, or McGivering something to get it working while in the field. I love stories like this. What's your most memorable time(s) where you had to get creative and use the spitball, bubble gum, paper clip, hammer, duct tape, etc method in a pinch?