Go on a personal odyssey, and amaze and impress your friends without taking any real risk:  bicycle solo across Europe, North America or other large land mass.

This is easier than it looks.  Unlike a marathon, kayak crossing or other iconic physical achievement, a person of healthy weight and minimal physical conditioning need not train or learn special skills.  Just start pedaling.  Don’t worry about distance.  I guarantee you’ll be in shape in a few weeks.

You don’t need an expensive bike.  I’m partial to 1980’s-era touring bikes, because they are indestructible, last forever, and cost under a hundred bucks in good condition.  But anything with at least 32c width tires will do.  

You don’t need expensive equipment.  Install front panniers, loaded with food and a single change of clothes, and start pedaling.  Bring a cheap netbook, and spend at least a few evenings at wifi-enabled motels, so you can google questions as you think of them.  You will discover quickly what you need, and, more often, what you don’t.

When I bicycled from California to Florida years ago (4500km), I constantly encountered middle-aged men who said wistfully, “I wish I had done something like this.”  My answer was always the same.  Nearly anyone can afford it, and nearly anyone is physically capable.

You can do it.  Just start.