STEALING BY NUMBERS

Wise guys call it "the magic box." It's the hottest item in the underworld high-technology arsenal--and the feds' worst nightmare. This cigarette pack-size gizmo threatens to send the wiretap the way of the FBI fedora. It sells for about $1,200 from some mail-order electronics distributors in the U.S. and the U.K. Cabled to a cellular telephone, it allows a bad guy to change his cell-phone number every three or four minutes with just a few keystrokes. Says Secret Service agent Robert Weaver: "The criminal can become a needle in a haystack electronically."

--By Elaine Shannon/Washington