The Google Earth 5.0 lets you navigate Ocean, now Google SketchUp team built a series of 3D models to highlight the new Ocean layer. Just install version 5.0, turn on 3D Buildings layer, and download kml file. The tour will visit models such as the Titanic, Batttleship Bismark, Aquarius underwater laboratory, as well as other submarines, shipwrecks, and dive destinations. You can also find these models in the Google Earth - Ocean Layer collection in the Google 3D Warehouse.