A friend used go out into the gulf of mexico in his Hobie (I thinks that's the name. Basically a kayak powered by bicycle like pedals and a propeller), until a shark bigger than his hobie boat swam past him. He was too chicken to go out in the craft again.
The two oddest sharks would be the Megamouth ( a plankton filter feeder not as big as the basking and whale sharks, but with an excessive big rubbery mouth, and the "cigar shark" aka "the cookie cutter shark". The cookie cutter shark is less than a meter long but instead of devouring game it simply takes a chunk out of you and runs away. Its bandsaw like teeth cut a nice plug of meat out of the hides of bigger fish, or human bodies, or of the plastic sonar domes on submarines. Their work looks as precise as that of a cookie cutter.