The carrot is an attractive one. Travelers can book a room at one of more than 150,000 properties around the world, pay the same as what they would using Expedia, Travelocity, Orbitz, or the hotel directly, but earn loyalty points or frequent flier miles and transfer them into one of 11 loyalty programs such as American Airlines AAdvantage or Virgin America Elevate. And if you don't care about miles you can even funnel points into your My Best Buy account and save up to buy stuff at the big box retailer. PointsHound's self-proclamation that it's "the most flexible loyalty earning platform on earth" just might be true. Co-founder and CEO Pete Van Dorn tells me any day members will also be able to rack up Bitcoin currency and in February the site will begin to offer points and miles for car rentals as well, with digital downloads possibly coming down the pike later, meaning users may someday be able to dole points and miles into various loyalty programs every time they download movies, music, or e-books. While a strong value proposition certainly helps with getting traction, here are several tricks Van Dorn says PointsHound employed to exponentially grow its member base. Get the full story at Inc.com