Couple of dumb stories for ya:

A parasail (oldschool mushroom style) required like 125 pound person to ride. My dad let me do it for my first time when I was about 8-10 years old, weighing ~70#. I was thinking, "yeah, sweet! Cool dad!" That was, until the wind came up, and even with the boat in reverse there was NO slack in the line . Can you say freaked out? he ended up going hand-over hand well over the 250 feet of line, since he lost it a coiuple times & had to try again it wasn't long before I was back up though, it is amazing experience!

Oh, a few years later the guy came for a test ride, and it was really windy. Dad told him it was a bad idea, but he wanted to go anyways. Long story short: rope broke, ended up in trees with a broken arm, and still bought the 'chute!