Okay, it was recorded ten years ago. I'll delete the post if everyone and their uncle has heard this thing already, but I swear it makes me smile every time.
For those of you not in the know, the 'Bloop' was a sound picked up on underwater microphones that were installed in the 1960s to spy on soviet submarines. Usually they'd get the sounds of underwater earthquakes, nearby whale calls, etc - but then came Bloop.
This is the sound, sped up 16 times. Okay, yeah, it sounds like a fart. But that was sped up: the sound itself was a little somethin' like
this. From the info picked up on the microphones, the sound had patterns consistent with biological sources, not geological ones. Only it's much, much louder than any sound ever made by even the largest whales. And it comes from /real/ fuckin' deep.
The wiki with links to articles and whatnot. I was thinking about posting the "immortal jellyfish" tomorrow - has anyone heard about that one yet? There aren't any particularly awesome pictures, but their life cycle kicks ASS.