We've talked about the big hot mess that is copyright law before, but I thought you'd dig hearing about a specific example -- with a happy ending for all!
A nifty site I discovered is the National Archives Experience's Digital Vaults (digitalvaults.org), where you can shuffle through primary source material like a deck of cards. How else would I come across a creepy (ha!) gem like this one?
That has horror movie written all over it, I'm telling you.