Aside from the home office furniture business, according to a report, one niche market that home workers are popularizing is the development of live-work condominium units.

"Live-work condos are a niche market, but they are, in certain circumstances, attractive to some people," says John McIlwain, senior resident fellow for housing at the Washington-based Urban Land Institute.

There's no doubt that working at home is a growing trend. In 2000 the U.S. Census found nearly 4.2 million people age 16 or older worked at home most days during the week, up from 3.4 million in 1990. That 23.5 percent increase over 10 years almost doubled the growth rate of the overall work force. The Census Bureau's most recent estimate, made from community surveys conducted in 2003, raised the number of home-based workers to 4.5 million - an increase of slightly more than 7 percent in only three years.

What exactly is a live-work unit?

There's no single definition of what constitutes a live-work unit.

"In some cases, they simply have an extra room that can be used as an office or a bedroom," says McIlwain.

The Metropolitan, a condo project under construction by Hoyt Street Properties in downtown Portland, Ore., offers prospective buyers a range of possible floor plans to help them visualize possible uses, says Marilyn Andersen, Hoyt Realty Group's principal broker. Those uses range from a contemporary office with several workstations to a small office within a home.