James Cameron a man who likes his diving is doing some diving again, this time for Avatar 2. As many are aware, quite a bit of Avatar 2 will take place underwater. Currently Cameron is commissioning engineers to build him a 2 man Sub to take him 10,972m to the bottom of the Mariana Trench in the Western Pacific. According to Canoe.ca the sub will be fitted with a heating system and 3D cameras to capture footage for the sequel which should arrive around 2014. The sub is half built at the moment and the last time someone went to the bottom of the Marina Trench was back in 1960.
The trench itself is the deepest part of the worlds oceans and and Wikipedia points out that if we horsed in Mount Everest, there would still be 2076m of water above it!