The EFF reports that color laser printer output contains trackable digital watermarks. I doubt this “feature” is listed on the outside of the box. (“New and improved! The government can identify every page you print!”)
The EFF’s work follows a PC World article from last Fall, which had escaped my notice until now, perhaps because I’ve been busy composing notes of encouragement and support to your President by arranging letters cut from random magazines and gluing them onto scraps of paper rescued from the recycle basket at distant Kinko’s: Government Uses Color Laser Printer Technology to Track Documents
So until somebody slips tiny RFID molecules into my glue stick, I guess I’m still anonymous.