CYBER SECRETS (This week on Life on the Internet) Law enforcement agencies say that in the wrong hands, email encryption software called PGP (Pretty Good Privacy) threatens the public good. Check out the online transcript, hyperlinks and live video stream of this week's feature "Cyber Secrets" on the Life on the Internet web site. <http://www.pbs.org/internet/> The program *Life on the Internet* is broadcast on Saturday mornings in some areas. Check your listings.