Here's a happy recent pickup - the Great Lakes Exposition, held in Cleveland during 1936 and 1937, didn't have a post office, but that didn't stop someone from trying to send a letter to an exposition visitor. This is only the second example known of the "Great Lakes Expo." handstamp. There are plenty of souvenir cachets from the exposition (it even had an official director of cachets, Mark Emsley.
The recipient, Henry O. Meisel, was a cover collector (well known as a cachet maker and a collector of meters), and also known for his long motorcycle tours of the U.S. But this isn't really quite "philatelic" - the letter (still present) is from Meisel's mother. I'll write this up for a future issue of the Ohio Postal HIstory Journal.
