Halfbakery: Shred-o-Scan
http://www.halfbakery.com/idea/Shred-o-Scan
"As the name suggests, it is a combined scanner and shredder. Basically, the scanner has "transient" memory of say, 30 seconds. If you shred something by accident, simply press the "oops" button, plug in the USB cable, and retrieve the document."