Q: Think of a 10-letter word that names an invention of the early 20th century and includes an A and an O. Remove the A. Then move the O to where the A was, leaving a space where the O was, and you'll name a much more recent invention. What is it?
Did one of these inventors come from Chicago?
Edit: The hint was a reference to the song "Mr. Cellophane" from the musical Chicago.