(WARNING: There are several usages of profanity in this video as the shark approaches the swimmer. Viewer discretion is advised.)
In this video a man straps on a GoPro camera to make a leap from some rocks into the ocean. As the man comes up above water he hears his friends shouting from above, and seconds later he gets very, very close to a large shark.
According to the video's description on YouTube, the encounter was with a great white shark near Manly Jump Rock in Sydney Harbour.
Full video: