Google in collaboration with the Great Barrier Reef Marine Park Authority let you explore the largest reef system in the world, and provide map data and updated satellite imagery of the islands, reefs, cays, and rocks in Google Maps.

In line with the goals of the International Year of the Reef 2008, the addition of the Great Barrier Reef to Google Maps will help strengthen awareness, improve understanding, and generate action to help conserve our international treasure. If you're lucky enough to have visited the reef, enjoy reliving your memories. If you've not yet been, happy discovering.

More info:Google Australia Blog