(FORTUNE Small Business) – Stampp Corbin does not seem like the type of man who would deal with somebody else's junk. The 44-year-old is seldom seen without suit, tie, and designer glasses. He drives a BMW, has degrees from Stanford and Harvard, and speaks fluent French. Yet Corbin has built a multimillion-dollar business by turning other people's trash--specifically electronic trash--into treasure.

Corbin is the founder of RetroBox, a Columbus-based firm that helps companies get rid of IT assets such as PCs, printers, and servers. The equipment can be both a security risk (because of proprietary information still on the hard drives) and an environmental hazard (because of the toxic materials hidden in each box). But RetroBox wipes the machines clean of all data, refurbishes and sells any that are still useful, and makes sure the rest are disposed of safely.

RetroBox was launched in 1997 when Corbin's other company, a tech consultancy called Resource One, was asked by a big telecom firm to help it dispose of some obsolete workstations. "I made four times as much handling the old stuff as I did the new," says Corbin. In its first full year RetroBox took in $150,000 in sales; by 2004 revenue had climbed to $14 million. That's average growth of better than 100% a year, but the demand for such a service is still increasing: Corbin is opening a new processing center in Phoenix this month, and he expects his volume to nearly double this year.

RetroBox is enviably positioned to take advantage of its booming market. It's bigger than the mom-and-pop recycling shops that cater mostly to consumers, yet smaller than manufacturing behemoths such as Dell, Hewlett-Packard, and IBM, which have all started helping customers get rid of unwanted PCs. Recently Dell outsourced its disposal programs via partnerships with companies that included RetroBox.

Some environmental statutes could help too. No federal policies specifically address e-waste, but about 40 states have laws on the books. Maine and Massachusetts ban dumping lead-laden cathoderay tubes from monitors into landfills.

Corporate customers pay a flat fee upfront for RetroBox to pick up their old equipment, which can range anywhere from a single small order to 75,000 items in a year. (RetroBox accepts computers from individual consumers too, but they usually must pay for shipping costs.) Items are priced according to the age, condition, and amount of gear, which works out to roughly $35 to $45 an item. That includes logistics and transportation, hard-drive sanitizing, and responsibility for any environmental risk. (Computers contain more than 1,000 materials, including toxic gases and toxic metals such as cadmium, lead, and mercury.)

Typically, when RetroBox receives the equipment, it is still loaded with software and corporate information, despite most companies' best efforts to wipe that data clean. Every piece is audited and inventoried, and sent to the company's Columbus-area warehouse--the size of two football fields--where it is stripped of all software. RetroBox's 20 technicians then work around the clock testing the equipment to see whether it can be salvaged. They make sure that the machines will boot, they run diagnostic software, and they wipe each hard drive three times, a technique Corbin cribbed from the military. If the equipment is too antiquated to be reused, it is dismantled. The components are physically shredded into bits and shipped to plastic and glass recyclers. All metals go to smelters, where any precious metals can be extracted.

About two-thirds of the equipment that RetroBox takes in is refurbished and resold; the original owner decides where it ends up. Occasionally the company takes the equipment back and redeploys it. ChevronTexaco recently replaced all its IT equipment companywide. It sent 30,000 components to RetroBox. About half of the items were not salvageable, but the rest were shipped back to parts of the company where new equipment was not needed. Vaneesh Kapoor, an IT product manager at ChevronTexaco, estimates that RetroBox saved the company $1 million in purchases.

When refurbished equipment is sold on the open market, the original owner gets most of the money, and RetroBox takes a cut of 25% to 30%. That means the firm makes money when the box comes in the door and when it leaves, and corporate clients come out ahead too--their equipment is disposed of safely, and they get some money back if RetroBox can find a buyer for it.

Corbin continues to develop partnerships with computer manufacturers, and he is securing more financing from private-equity firms. When asked how it feels to have all those projects in the works, he whips out a food metaphor.

"Let's pretend I'm making soup. If everyone throws in a potato, you get potato soup, which I love," he says. "But if someone throws in shellfish and a little rice and some green peppers, well, you get jambalaya. And I think jambalaya is a lot more interesting."