Chip and PIN

The possibility of interception attacks on isn't new
http://www.lightbluetouchpaper.org/2006/03/15/chip-and-skim/

However, not only is it possible to tamper with readers large numbers have been tampered with "either during the manufacturing process at a factory in China, or shortly after they came off the production line":
http://www.schneier.com/blog/archives/2008/10/new_chip-and-pi.html