Nelson, self-described as "a guy who had way too much fun", has a lunatic appetite for having a good time. And a good time he has, whether rafting the Omo River in Ethiopia, scuba-diving in the Marshall Islands, walking on hippos in Tanzania, or cavorting with penguins in Antarctica. (And let us not forget the skydiving, hand-gliding, and hot-air ballooning.) Prepare yourself for one hell of a ride.