In the spirit of those mysterious sounds you hear on shortwave radio late at night (like numbers stations, morse code, etc.), I created a sub-site quite some time ago where you can experimentally generate audio-encoded sound clips of text and numbers:
user link on signals.nitrocosm.com
It's not exactly the most practical thing in the world but it's kind of fun to play with it. Then again, maybe I'm just being a huge ham radio nerd.
In addition to that, this collection of audio files is automatically generated from the same backend library as the above link:
user link on tmc.nitrocosm.com
It's just as nonsensical in terms of purpose. Eventually I'm going to do something interesting with encoding small amounts of data from somewhere in these files.