As glued to the net as we all are, there's vast quantities of content that is not available online.
Hack let you convert encrypted Mobipocket files that were intended for another reader so that that work on Kindle.
Hacker Igor Skochinsky used DRM to load Mobipocket books onto his Kindle. Using a series of scripts, he's able to convert eBook files to Amazon's AZW format and then add the necessary serial number DRM, specialized per an individual's particular Kindle.
Use Mobipocket software to convert PDFs to that format so you can read them on Kindle.
A revolutionary portable reader that wirelessly downloads books, newspapers, magazines and blogs to a crisp, high-resolution electronic paper display that looks and reads like real paper, even in bright sunlight.