Diana Nyad
At the age of 64, long-distance swimmer Diana Nyad made history back in 2013 when she became the first person to complete the 110 perilous miles from Cuba to Florida without using a shark cage. This was Nyad’s fifth attempt since 1978, and she had a bit of luck with favorable currents and fewer of the toxic jellyfish that had contributed to the failure of an earlier effort.

The swim was with significant difficulties, though. She had sunburns, seawater-swollen lips and tongue, and mouth abrasions from a special silicone mask designed to ward off jellyfish. How much money would it take to convince you to try pulling this off? Let us know back in the comments.