Google Street View includes views from under the Earth's oceans. You can tour shipwrecks, swim with humpback whales, and virtually dive down to dozens of coral reefs.
P.S. You can also climb Yosemite's El Capitan on Google Street View, which is SO OMG TERRFIYING THAT I CANT BE BOTHERED TO CORRECTM Y TPYING. Are anyone else's palms soaking wet right now? (via mr)