If William Shatner were to start crooning again for Priceline.com (NASDAQ:PCLN), I would suggest something along the lines of Gold Diggers' "We're in the Money" or AC/DC's "Back in Black." The online travel agent has become another profitable, sustainable dot-com business, and it's got no plans of slowing down.

Earning $0.13 a share during the March quarter on a 46% spike in gross bookings, the company continues to expand its offerings. As just one example, Priceline's rental car reservations jumped 83% over last year's showing.

Yes, we've seen this before. Priceline once figured it could slap its "Name Your Own Price" model on everything from groceries to gasoline. It failed that time out, but now the company is taking a more logical approach to diversification.

Priceline has grown, in part, by acquiring proven upstarts, most recently scooping up a majority stake in Travelweb.com. That gives the company a more traditional hotel-booking portal to go along with its deeply discounted namesake service. While TravelWeb will post a loss for the current quarter, Priceline expects the purchase to be accretive to earnings next year.

InterActiveCorp's (NASDAQ:IACI) Expedia and Sabre's (NYSE:TSG) Travelocity have proven that you can carve a cozy living booking travel on the Web. Orbitz (NASDAQ:ORBZ), which reports its results tomorrow morning, still has a way to go before catching up but looks headed in the right direction. Last year, we launched our Travel Center as a result of the growing interest in the convenience of planning trips online.

That's why buying a stake in Travelweb from the hotel companies that founded it makes sense. In the early days, Priceline was sending rejection notices on five of every six bids it received. Now it will have an established Web portal to serve as a more photogenic "Dear John" postcard.

Along with Hotwire and Cendant's (NYSE:CD) CheapTickets.com, Priceline has proven that you can turn a profit serving bargain hunters with packed suitcases. Now it continues to lay the groundwork for a solid future.

Given management's projections for the next few quarters, Priceline should earn between $0.76 and $0.90 a share this year. The stock has shed nearly 40% from its last year's highs, and the earnings horizon looks bright.

There comes a time when one can make a decent valuation argument in favor of Priceline. That time -- for those looking to "Name Your Own Price" -- is now.

Have you made the trip to our new Travel Center yet? Which sites do you use when you need to book a flight fast and at the best fare possible? Have rising fuel costs jacked up discount prices? All this and more -- in the Cheap Air Fares discussion board. Only on Fool.com.

Longtime Fool contributor Rick Munarriz has been booking his travel online since the 1990s. He has a favorable outlook on the industry, but he does not own shares in any of the companies mentioned in this story.