AT&T, for example, imposes a $325 "activation fee" for each wiretap and $10 a day to maintain it. Smaller carriers Cricket and U.S. Cellular charge only about $250 per wiretap. But snoop on a Verizon customer? That costs the government $775 for the first month and $500 each month after that, according to industry disclosures made last year to Rep. Edward Markey, D-Mass.