It's a great idea: Take a digital photo of a document, open book, or even a meeting whiteboard, then use Snapter to make it look as though it were scanned with a flatbed scanner. In my tests, though, I wasn't impressed.
The Snapter folks say that their product "Rotates, crops, stretches, solves per-spective [sic] problem, sharpens the image and improves color." In my tests the program did indeed rotate a photographed document a bit and crop away much of the background. It appeared to improve the contrast, too. However, it also made the text fuzzier than it was in the original digital image. I probably could have gotten better results doing these tasks myself with a free image editor like FastStone Image Viewer or Gimp.
However, if you're not handy with an image editor, Snapter may well be useful. You can download the free 14-day trial to see if it meets your needs. The program remains functional after that time, but it starts to add a watermark onto your images. You'll need to shell out $49 to avoid this. (You'll see an option for a $20 Lite version within the program itself, but that appears to no longer be available.)