If you like typewriters or tap dancing, this scene from "Ready, Willing, and Able" (1937) is bound to bring you a smile. The dancers, who must have risked breaking an ankle on those keys, are Ruby Keeler and Lee Dixon.
I was reminded of the scene by this still which is currently being auctioned on eBay.
Here's a photo taken a few moments earlier or later that Robert Messenger put up on his blog:
I want a typewriter with that Deco styling!
And here's a link to the 1970 Bollywood version of the idea, if you haven't seen it.