Apparently, even if you don't put your name on your copies, it's possible they can be traced back to you by tiny dots on each page.

This article states:

Researchers found patterns of yellow dots arranged in 15 by 8 grids and printed repeatedly over every color page, said Seth Schoen, a staff technologist at the San Francisco-based civil-liberties group.

The dots are visible only with a magnifying glass or under blue light, which causes the yellow dots to appear black.

By analyzing test pages printed out by supporters worldwide and by staffers at various FedEx Kinko's locations, researchers found that some of the dots correspond to the printers' serial numbers. Other dots refer to the date and time of the printing.

How super secret can these documents be if people are copying them at Kinko's? I'm pretty sure that's where James Bond goes when he...

Oh wait, did they say Kinko's? Hang on, I have to go shred some color buttprints...