Back in 1981, after airline deregulation became a fact of life for a once-hidebound industry, a new airline began serving cities on the East Coast. People Express launched with what then were incredibly low fares, drastically undercutting the major airlines on the routes it served. The people who flew on People Express weren't just the travelers who would have paid high fares on the old-line carriers. They were also an entirely new breed of air passenger: folks who had once driven or taken the bus. Now consider the new breed of advertiser in the online world. Google's text ads, which pop up after someone searches using keywords, cost in most cases a small fraction of what it would cost to advertise in a local newspaper or broadcast outlet. other words, Google and the other companies in this space are attracting ads from businesses -- including businesses that are as small as one person in a home office -- that in many cases never advertised before. The potential for this is larger than most people have recognized. In theory, the Net-based advertising market is almost unlimited -- extending to any one person with any one thing to sell. [San Jose Mercury News]