(FORTUNE Small Business) – Forget Sand Hill Road—Oprah's mouth is the new path to cash. "She went wild over my curried-chicken sandwich," says Margaux Sky, 50, whose Art Café & Bakery in San Luis Obispo, Calif., was saved when Oprah impulsively cut Sky a check in June. The buzz from Oprah's appearance quadrupled the café's business the next day—one of many recent cases showing how basking in the reflected glow of a celebrity can generate a huge sales spike for an entrepreneur. Not surprisingly, there is a young and growing industry devoted to conducting the goods of small businesses to the hands—and mouths—of celebrities. Here is a sampling.

BACKSTAGE CREATIONS of Santa Monica brings clients face-to-face with celebs at award shows by building a large product room six to ten feet from the stage. Inside, clients pile products and send reps to pitch and mingle with stars. FEE: $1,200 to $100,000.

SUCCESS STORY: After Sarah Michelle Gellar was spotted carrying a California Leash Co. purse, the company's sales soared, letting it boost production from one style to five. This year Paris Hilton grabbed one, and the company got a meeting with Fred Segal, a high-end L.A. boutique. "Once we got the celebrity, we got credibility," says co-founder Amber Ozinga.

A&R PARTNERS of San Mateo, Calif., turns techie clients into movie stars by setting up meetings with the prop crews of major film and TV studios. The company places clients' products on such shows as Law and Order. FEE: $5,000 to $10,000.

SUCCESS STORY: iRobot makes the Roomba, a robotic vacuum. "But you have to ask, 'What celebrity cleans her own house?'" says Kathleen Williams, a senior manager at A&R. So at VH1's Big in 2003 Awards, iRobot gave redeemable gift cards to presenters' families—35 family members cashed in, including Katie Holmes's mom. iRobot credits that exposure with getting the Roomba in an upcoming movie.

BUZZBAGS of New York City stuffs gift bags with clients' products and distributes them at celebrity parties and hangouts. FEE: $500 to $5,000.

SUCCESS STORY: Amy Schwab used BuzzBags to launch her accessories company. After 20 of her fabric belts were included in the bag for this year's Oscar nominees, Schwab got coverage in two local papers and a compliment from Hilary Duff. "It boosted my brand recognition with retailers," says Schwab. —MAGGIE OVERFELT

THE O FACTOR: "If Oprah says, 'I love this,' you're golden," says Karen Bromley, co-founder of New York City's Bromley Group, which nabbed a spot on the Big O's Christmas show in 2000 for client Ugg Australia. Sales of Ugg's furry boots jumped 400% over the next three years. But as a measure of Oprah's growing clout, not even her titanic influence on book sales compares in scope to September's $7 million giveaway by General Motors, which donated 276 new Pontiac G6 sedans to Oprah's entire studio audience.