A case of chemicals showed up at my shop. I open it up and it's called Nuts Off. Seriously. Shortly thereafter I get a bill for $400 for 12 cans of it from some outfit in New Jersey than I never heard of. I tell them I didn't order it, and they will need to send me a UPS tag if they want it back. They threatened to wreck my credit and sue me if I didn't pay for it. I told them to put that in writing, and it's the last I heard of them. I guess it works OK, but I saved the last can just so I can say, "Hold on a minute, let me get my Nuts Off."
While WD-40 is not the world's best penetrant oil, I can't live without it. Recently it saved me several hundred dollars. I was driving my wife's truck (pretty truck) and some ahole left a full can of spray paint in the road right around a turn. Since I was going fairly slow when I hit it, it hosed down most the truck with paint. I drove home as fast as I could, and grabbed two cans of WD, and started hosing down the truck ASAP. After about an hour, all of it came off (except the undercarriage and tires).
It also:
Takes off road tar
Kills bugs
Removes Duct Tape residue
Spray it on before the drags, and it will help keep burnout rubber off the body, and helps remove it if it does stick
Or if you use Vasoline to keep the rubber off, it cleans the Vasoline.
Cleans and preserves granite surface plates and measuring tools.
Allows you to move very heavy tooling on granite plates
etc
etc