Wow, what a little beauty. I love vintage gadgets. I used to sell them on eBay - I'd find them at a car boot sale or something, mess around with them and if they work, sell them for profit :) Some people didn't even care if they worked or not, they just needed them as some kind of art deco or so. I think I even sold something to a movie company (probably trying to recreate a historical period).
Basically if you ever got tired of it, you could flip it on eBay probably for more than £15 :)
a friend's son who is into experimental music has already said he wants it when I'm bored with it! Apparently they're considered a musical instrument now...