As glued to the net as we all are, there's vast quantities of content that is not available online.
Use Mobipocket software to convert PDFs to that format so you can read them on Kindle.
Kindles can read a variety of non-proprietary, non-DRM'ed formats. They read TXT, HTML, JPEG, and non-DRM Mobi files directly.
How do you load other eBooks onto the Kindle? Just add Amazon DRM.
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.