Hired by ForbesTraveler.com to review some of the most luxurious accommodations on Earth, and then inspired by a chance encounter in Dubai with the impoverished workers whose backbreaking jobs create such opulence, Bob Harris had an epiphany: He would turn his own good fortune into an effort to make lives like theirs better. Bob found his way to Kiva.org, the leading portal through which individuals make microloans all over the world: for as little...