Wow! Amazing story in the NY Times today, about a phonautogram, a visual sound recording made on an early phonatograph, which researchers recently decoded and were able to play. The most incredible thing about this recording is that it's from 1860!
I'm not even going to try to explain this amazing development, but do read the article and marvel at how modern scientific and computer technology enabled the world to hear again the voice of someone living nearly a hundred and fifty years ago. You can actually listen to some of the recording, too.
If this kind of a story isn't enough to get your imagination going, nothing is! I think it's just astonishingly neat!
For more information on the phonaugraph and other early recording devices, check out this nice primer on Wikipedia, which I find is a great place to start research on almost anything!