Robert Rhue took the plunge a little over 1 1/2 years ago. On a vacation to Jamaica, he squeezed into a wet suit, strapped on an oxygen tank and dove about 30 feet in the clear tropical water. He was ...

Opinions expressed by Entrepreneur contributors are their own. From the moment I took my first breath underwater as a scuba diver, I fell in love with the world that lives beneath the surface — I find ...