Actually, the story all us rocket scientists were told was that WD-40 was developed for the Atlas missile, which featured very thin-skinned propellant tanks made from stainless steel.  So thin, in fact, that you could not stand it upright unless it was pressurized.  The WD-40 was used to keep it from rusting.  They still use it today for that purpose but I'm sure the folks working on it now don't really know, or have proof, that it was developed for their program.

- "Rocket Rob" Wolf
LNC2 70%