Plenty of free e-books in Mobipocket format show up fine on Kindle.
Granted the PDF converter seems to have some trouble with graphics PDF's, but for books the converter works very well.
Being at home on a rainy day, but wanting to read some new novel that just came out, you can have it in seconds. This concept (not hobbled by DRM) is pretty damned liberating.
The Kindle supports Mobipocket files directly. You don't need to write a script to do that.
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.