but what they were doing was they were automating the middle man. >> 600 million hits a month. >> that's right. >> that's a lot of people. >> that's right. >> how do you stop the unscrupulous? >> problems like that are really very, very rare on ebay. it's all based on trust. >> one thing ebay pioneered is this idea that we rate each other. so that future transaction participants can see whether you're a good person to deal with or not. it's in your financial interests to be looked up to and respected as a trustworthy transactional partner. >> on nbc news in-depth tonight, we're going to talk about the superstars of the stock market, those red hot internet stocks. companies that in some cases didn't even exist a few years ago are now trading in the stratosphere. >> the whole dotcom bubble of the late '90s was based on this idea that what counted was not profit. what counted was eyeballs. if you could get enough people using your stuff, you would figure out a way organically from that to make a profit. >> the daily volume, 3.7 million shares.