Just call Dave Balter the Buzzmaster. The 33-year-old founder ofBzzAgentInc., a word-of-mouth marketing agency in Boston that projectssales of $10 million to $15 million in 2005, is so good at talkingup products and services that he’s got 92,000volunteers–dubbed BzzAgents–talking up his clients.

Operating on the premise that people are looking for goodrecommendations before they buy, Balter gives his agents access tothe latest and greatest products and services. BzzAgents test themout and then chat them up to friends, neighbors–even strangers.They’ll sing the praises of everything from satellite radio toapparel to candy. Then, they report to BzzAgent with the results oftheir efforts.

Why does it work? “As consumers, what we search for iscredibility,” says Balter, whose book Grapevine: The New Art of Word-of-MouthMarketing is due out next month. “A recommendationfrom another person is a form of credibility.”