Aaahh, I've dived with sharks lots. Safer than driving in your car, that's for sure! The largest were 12-14 foot Lemon Sharks. They have the capacity to do you some damage, so it is an unusual feeling when they are headed toward you.
I was more frightened by diving with seal lions. The male seal lion made it VERY clear that he didn't want you bothering his harem. He was very fast, very manouverable and very threatening!
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400 gal reef. Established April, 2007. 3 Sequence Dart, RM12-4 skimmer, 2 x OM4Ways, Yellow Tang, Maroon Clown (pair), Blonde Naso Tang, Vlamingi Tang, Foxface Rabbit, Unicorn Tang, 2 Pakistani Butterflies and a few coral gobies
My Tank:
http://www.canreef.com/vbulletin/showthread.php?t=28436