EFF decodes secret color laser printer spy markings

[utln]

The top and left rows are used as parity bits, for error correction. The remaining dots in the grid are used to convey information about the document and its source, including printer model, printer configuration, printer serial number, and the date and time the page was printed.

http://arstechnica.com/news.ars/post/20051018-5447.html

[DigeratiPrime]

incredible. remember reading about this on slashdot a while ago. gj EFF!

http://www.eff.org/Privacy/printers/docucolor/

Edited October 18, 2005 by DigeratiPrime