Forever Blue is a new Wii game that lets you navigate through the deep blue sea with your remote. You're a deep sea diver, and you're surrounded by whales, sharks, manatees, and all kinds of giant, cool sea creatures. You start on a diving boat that takes you out onto the water—then you step into your gear and go..
See a clip (with added Enya music) on Youtube here
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The BBC developed something called Dinosaur World, which used the same graphics engine as Walking with Dinosaurs, about 6 years ago. Dinosaur World had a concept very similar to Forever Blue (although it was never fully released) - essentially you roamed around a 3-D island exploring the prehistoric vegetation and animals.