Entrepreneur Don Sorkin is fighting crime with a smile. His customers' smiles, that is, which he places on personal checks to combat fraud, theft, and forgery. For $24.95, Photo Safety Checks, in Los Angeles, will provide you with 200 checks and deposit slips with your picture on them, printed on special paper that reads "VOID" in the background if reproduced. "This will make a criminal think twice," says Sorkin, who launched his venture last January with private start-up funds in the six figures. He reports that sales of his checks have been "steady and progressively picking up" since their introduction; his plan is to capture one-quarter percent to one-half percent of the estimated 100 million personal-checking-account holders in the country, or between 250,000 and 500,000 customers.

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