Xtreme Commerce

You wouldn't imagine Steven Rothschild, the slightly wonky entrepreneur who founded Furniture.com Inc., as a great storyteller. But the 40-year-old really fits the bill with the tale about how he came up with his latest online venture. At home one day, his wife began complaining about what a pain it was to find lightbulbs for their dog pen. That's when the entrepreneur saw, er, the light: bulbs.com, an online service that sells just bulbs!

That's not to be confused with Justballs!, mind you. Justballs!, which is a seven-month-old startup, sells more than 1,700 balls for sports, from $1.95 Spaldeens for stickball to $199 billiard ball sets. Then, of course, there's eBags Inc., which specializes in sporting, business, and travel bags. And Shovels.com, Sunglasses.com, and WebTea. Guess what they sell.

What's going on? Extremely vertical e-merchants are bucking the trend of such companies as Amazon.com Inc. and the shopping areas on portals devoted to the widest variety of products imaginable. With extreme verticals, the point isn't to offer a wide range of products, but a lot of the same thing. Bulbs.com, for example, says it plans to have 5,000 different types of lightbulbs out of an estimated total market of 7,000. Now, that's extreme.

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