the bermuda triangle
Keep up the levity Walt or you''ll turn into a pocket protector like Jeff H!!
I just saw a Discovery channel special on the Bermuda Triangle mystery, current theory is that this area of the Atlantic contains a lot of natural gas deposits (funny I do too) and from time to time, there are huge eruptions of natural gas from the sea bed causing enormous bubbles that can change the buoyancy of a normally sea worthy vessel, causing it to sink.
Like those elusive Weapons of Mass Destruction, these gas bubbles may be difficult to find!