You will feel more secure with a free (-ware) dose of Pretty Good Privacy.

Provides information about Phil Zimmerman's Pretty Good Privacy (PGP) freeware, a public-key encryption program designed to ensure personal privacy of various files on the Internet, particularly of electronic mail messages. United States government's conduct of an investigation into the PGP freeware; Merit of the government's Clipper chip approach to public encryption; PGP's system of operation.