Heller says he needs only two hours a week for investing--all he can spare because he has turned his photography hobby into a business, traveling all over the world to shoot photos for tour company brochures.

FORBES: Investment Guide

Real estate billionaire Stephen Ross, owner of the Miami Dolphins, has a new hobby that he hopes will bring in some extra cash.

FORBES: Billionaire Stephen Ross' Hi-Tech Dream for the NFL

Mr. Irrizary, an 80-year-old, has more than 200 bikes he fixes and restores as a hobby.

WSJ: Showing Off Their Schwinns

Dave recently left the Army, and his hobby has now turned into the day job - he has just been offered a position with an aviation company.

BBC: Buzz Aldrin bids to help people with disabilities to fly