a2800276 writes: "The NSA has released some documents about Tempest in response to a FOIA request. They can be found over at Cryptome. Some are really old (dating between '75 and '95) and heavily redacted but interesting nontheless."
Five is a sufficiently close approximation to infinity.
-- Robert Firth
"One, two, five."
-- Monty Python and the Holy Grail