booking.com

In 1999, Priceline saw its stock surge to absurd heights before it had earned a cent in profit, and after the bubble burst, it lost more than 99% of its value. But from that low, the discount travel site began a hard journey to profitability that has proven there are second acts in dot-com companies' lives.

This summer, for the first time in five years, I used Priceline.com (PCLN) to book a hotel room and rental car. Turns out, I am part of a trend. The online travel agency saw an increase in bookings over the summer. Now it forecasts sales in the current quarter rising 28 percent from last year's...