I have had 3 good run ins with sharks sailing...
had a solid sized fin pop up in front of me at Sandy pt, had a BIG tiger shark circle 3 of us on SUP's at Kanaha in Maui and the best one was at Hookipa where I was planing along full speed when a fin popped up about 3m in front of me... I couldnt avoid it and ended up hitting right in the back! was a pretty solid sized tigershark.. The shark shi# it self as much as I did and thrashed it's tail around on the surface and took off... that was as close as I want to come to one of those again. I didn't even get any cool marks on my board :(
check this one out from a few weeks ago... I was fishing off Bermagui and i started filming a baitball with all these seals feeding. Just stuck my GoPro on a pole and stuck it underwater... checking the footage later - there was about a 4.5m White pointer under the school!!!