Well, I rode Downhill mountain bikes for about 10 years. Rode all sorts of ridiculous terrain and man made obstacles. Good times...
Now I'm into freedive/spearfishing. Less apparent danger, but I've had a few "interesting" encounters. A few with big 3 meter wide Stingrays, and a few with sharks. I've had a tug of war with a 2 meter Wobbegong shark over one of my fish, and had a 2.5 meter Blue shark cruise past me. But then there was that time I got approached by two inquisitive Dolphins, most memorable experience to date.
What was your closest near death experience?