Even before last week's attacks, security experts like Mr. Brumley were routinely capturing and archiving conversations on chat channels with the purpose of saving the information so it could be correlated against other data in tracking computer criminals.

Technology has improved, allowing authorities to capture conversations on e-mail and instant messaging that makes it easier to establish that information has been passed around.

The Supreme Court held that conversations are protected by the Fourth Amendment, and that the use of electronic devices to capture conversations thus constituted a "search."

The tapes also capture conversations about nuclear weapons - Mr. Eldawoody has a bachelor's degree in nuclear engineering - and about obtaining nuclear materials from the Russian mafia.

Investigators eventually placed listening devices in the Lepores' home in Florham Park, and were able to capture conversations between family members, people close to the case said.

In between songs, the film briefly captures conversations between band members.

Ramsey brought his tape recorder on the field to capture conversations and statements.

The Creative Vision documentary captured raw conversations of people mesmerized by the artwork.