It was suggested to me that I post this in your sub-forum.
I help out with the Underwater Videographer Podcast. This week's is a very strange and unusual podcast. I interviewed Dr. Robert Schoch from Boston University. He was involved in a History Channel Special on the Yonaguni Underwater Monument. Some say that this immense structure, 80 feet underwater, is artificially made and sculpted. Dr. Schoch comes down on that it is naturally formed.
Regardless, if you are looking for an exotic dive site to video, you may
want to check out the Underwater Videographer podcast at
Underwater Videographer.
By the way, unless I am mistaken, History Channel ran the special last week.
Also, by the way, not sure about the copyright laws on this, but the video
is up on Google Video at
Ancient Marvels Mysterious Pyramids at
Ancient Marvels Mysterious Pyramids