I've really been fastenated by early aftermarket signal devices that were offered in the late 30's and early 40's. I have the following 6V signal device on the back of my roadster. It's called a Fooey Face automobile signal device that was submitted for a patent in 1936 and was awarded a patent in 1938. You'd be surprised what you can pull up when you enter a patent number on the internet now days. Anyhow, you give it 6 volts and eyes light up red, the tongue sticks out, while making an obnoxious buzzing noise. I'd like to see what other clever signal devices people have found and restored over the years. Many of them have been patented so they have to be around. Dowie
Go to Google Patents, and you can do key word searching and find more stuff...and try searching the companies that made stuff like this as "assignee"...