PC World has an article on identification marks from color laser printers. Basically, most color laser printers (and perhaps other printers?) embed faint yellow dots across any page they print, and those dots encode the printer's serial number etc. So, if you use the printer to make counterfeit money, the government could perhaps trace the printing back to you.
The fear, of course, is that any old document could also be traced back to who printed it.
Posted by Tom Nugent at July 28, 2005 12:07 PM