^ here's another one. this is what I was thinking of originally. I have it on my kindles but never use it:
http://www.edukindle.com/2010/09/not...r-ideas-handy/
With scans, it's always a little sketchy since if you're going to convert them you have to OCR them first and pray that it works okay. Then pray again that they will convert okay.
And that's another nice thing about the DXG: you can skip that last step and simply scan them as a PDF.