
About 18 months ago, I heard a report on NPR about a 900-number
"1-900-STO-PPER" or some such, for placing untraceable calls.
You call them, and on "bong" tone dial the number you want to
call; they told the NPR interviewer that nothing short of a
court order (which they'd fight) would make them release their
records.                                                                   
                                            

Matt Healy
"I pretend to be a network administrator;
 the lab net pretends to work"