Did I miss the explanation of why the stamp is called the "inverted jenny"? Inverted, sure, but was the aircraft perhaps called a Jenny?

And speaking of other other-that-spinning jennies - there's also a kind of jib sail called a "jenny," which is a shortening of Genoa, the "official" name for that sail.

"Genoa Sail - Large forward sail that replaces the smaller jib and provides a very large increase in sail area. Like the jib, it attaches to the forward wire that holds up the mast (headstay), and sheets to adjustable blocks mounted on a track on the cockpit coaming. Shown on page 9 of the brochure", at
http://www.macgregorexport.com/sharpoptions.html, and other places