Animal planet has been going off recently: http://animal.discovery.com/tv-shows/mermaids/videos/mermaids.htm
So, saw one thread from back in april on this topic. Anyway, NOAA recorded some strange organic animal noises in the deep ocean that have never been heard before, they thought maybe it was a new type of dolphin or whale, this is called the bloop sample. Then starting off the coast of WA (fuck yeah) there was a mass beaching of whales due to US navy sonar testing. A body was found on shore by 2 local boys and recorded with shitty cell phone camera. The body was removed by government authorities before anyone else could examine it.
The navy denies this testing, NOAA had an audio recorder in the ocean near by the first WA location, it recorded the sounds of whales before/during/after the test, the sound of the test it self, and, the bloop.
Now before I go any farther, I would like to note that for all of recorded history, humans from all cultures have tales of mermaids. Drawings and other art work for centuries have depicted them. Fish have been caught out at see with spears in them. Sharks have been found killed with strange weapons still in them. And Fishing boats have reported sightings for as long as man has been at sea.
A corpse was found inside a shark off the coast of South Africa. it was the first time one had been examined by scientist outside of any government. As it was eaten it was only a partial corpse.
Then in march, a team off the coast of Greenland mapping the ocean floor for oil drilling caught this on 2 handheld cameras (this was live on animal planet so im having issues finding a clear video)
There is a lot more to this story obviously, if you have some time you should watch the animal planet shows on it. There is another humanoid species on earth still to this day, that is fucking incredible by it self, but that it lives in the ocean?! With a world that can only get smaller, its cool that there are still things out there we don't know about.