How in the name of all things holy have I lived this long without Fels Naptha soap? Not only does it come in a package that looks like it came out of a time capsule buried in 1944, and for less than a dollar...it removed an oil stain from my favorite pair of J.Crew khakis. That stain had been there for nearly a year, but I couldn't part with the pants, because they fit so well, and it broke my heart. Now they're clean again.
Fels Naptha is King.