I learned as a teenager to use it to clean the winshield of a car. It takes that layer of scum off that build up over time and makes the windshield cloudy and hard to see through.
Second use per the article. McDonald’s double cheesburger, fries and a Coke. Best HANGOVER CURE you can buy for $5.
An old pouch of roll your own tobacco did the same thing. Now I use rain X.
I have also used it as the first step to clean firearms that were funky before applying the Hoppes.