Wired writes in an article about the pending Lexmark DMCA case (reported here a couple of times, and basically dealing with the copying of a copy protection chip in a piece of hardware) and the potential effects if this case were to be won by Lexmark.
As many have postulated before, the problems with the DMCA's broad authority are immense, and may well leat the the introduction of "copy protection" or in this case replacement part protection in industries that people have for decades counted on.
One example is the automobile industry, where people are now considering the possibility that your next car may have a parts replacement protection chip installed in crucial (and expensive) parts such as transmissions. These chips would only allow the car to function if the chip from that particular manufacturer was in the replacement part. By using a "copyrighted" chip, the manufacturers would be able to prevent the use of spare parts from other manufacturers and therefore you couldn't get an aftermarket transmission for your car.