WD-40

In 1953, a fledgling company called Rocket Chemical Company and its staff of
three set out to create a line of rust-prevention solvents and degreasers for
use in the aerospace industry, in a small lab in San Diego, California.

It took them 40 attempts to get the water displacing formula worked out.
But they must have been really good, because the original secret formula
for WD-40—which stands for Water Displacement perfected on the 40th try—
is still in use today.

Convair, an aerospace contractor, first used WD-40 to protect the outer skin of
the Atlas Missile from rust and corrosion. The product actually worked so well
that several employees snuck some WD-40 cans out of the plant to use at home.