In the first week or so, the program had already discovered about 5,000 holy trinities, says CMU professor Latanya Sweeney, head of the project. On Wednesday, Sweeney will begin releasing the e-mail notifications. “This is going to be a really weird event,” says Jay Foley, director of the Identity Theft Resource Center, a nonprofit dedicated to preventing identity theft. He foresees a flurry of complaints directed at bureaucracies that have neglected to remove Social Security numbers from online documents. The biggest source of Social Security numbers, however, are résumés posted on job-search boards.

Sweeney hopes the Federal Trade Commission or private companies will one day use Identity Angel as a prevention tool. “We would love to be able to say, ‘Look at how many tens of thousands of people we saved from identity theft,’” she says. One drawback: there’s nothing stopping thieves from developing their own program–call it Identity Devil.