Internet activists will attempt to jam the infamous computer surveillance network Echelon as part of a protest on October 21.
Jam Echelon Day calls on Internet users to clog the monitoring system by using so-called "trigger" words in e-mail messages.
The Echelon system, which involves Australian as well as European and North American security authorities, is said to monitor the use of certain words such as "bomb", "hacker" and "terrorism" in all forms of electronic communication.
In May the European Parliament confirmed the existence of the Echelon spy network which was established in the 1970s and includes Australia. The Australian end of Echelon is reportedly run by Defence Signals Directorate, Australia's top-secret electronic intelligence gathering body.
Federal government officials declined to answer questions about the system at budget estimates hearings in June.
The protest is being led by a group called Cipherwar, which has posted a list of 1700 "trigger" words on its Web site.
A media statement on the Cipherwar Web site said the use of Echelon to breach privacy should be deplored.
"Now is a chance for anyone, regardless of computer expertise, to become an instant hacktivist - and all you need is your regular e-mail program and the desire to stand up and count," the statement said.