It's hard to argue with success, especially huge success. eBay was the first online auction site for person-to-person bidding, and it remains the top site. Some studies have estimated its market share at more than 80 percent of online auction sales in the United States. Now it is expanding overseas and tapping into the increasingly interconnected global economy. It should be a major force in e-commerce for many years to come as other cultures tap into the online auction phenomenon.