I was held up at gunpoint when I worked in an off licence as a student.
I was out diving on the Great Barrier Reef and jumped off the boat only to find a 3 metre hammerhead had decided to shade itself under our boat. It was about 4 or 5 feet away from me when I jumped in, and that gave me the biggest start I've ever had in my life..!
I had a few pretty major spills when I was cross country mountain biking when I was younger. The worst one, I misjudged a corner on a dirt track and stacked it into a tree. The bike was wrecked but I got away with a few bruises. Lucky escape there!
I had a few run ins with spiders in Australia as well. I was out horse riding in the mountains south of Brisbane and when you're on horseback, the golden orb spiders webs are about face height.... And they're big spiders, about 6" across. Fortunately the thing didnt bite me, and I took a stick from a tree to clear the webs after that. I also came across a few redbacks, which can kill you if you're not careful.