Share your ‘I MacGyver’d it’ solutions

Septic service wanted $2k to replace my crumbling D-box. Something about the acid dissolving concrete over time. I took two old plastic flower pots, put one inside the other, poured concrete cement into the 1" space between them. $2 for the bag of cement. First one crumbled to sand in 10 years. Now 20 years later this one is still strong as the day it was made- er, MacGyver'd.

Different colors of nail polish to paint bus-fuses.

My stereo at the time had only a mono sub out, but I wanted true stereo subs. I found out how to convert speaker level to line level, and now I have stereo subs. Not only is the music better with channel separation, it also serves to even out room response. Cost was a few bucks for a decent rca jack and a couple resistors.

I fought back against neighbors who blasted shitmusic from an outdoor stereo by using microwave oven parts in a homemade sheet-copper horn antenna to microwave and stop their stereo. I was in my last year of the coursework for my PhD in physics and math and used the university's expensive Mathematica software to optimize the dimensions of the horn antenna I designed. 

This was more than the statute of limitations of whatever laws I broke ago but when people try to report such things to the police they sound delusional so I was safe. 

I saw some MacGyver reruns my wife told me to watch and I would like to think MacGyver had a doctorate in the physics and/or engineering that made him able to invent his weapons.