- Many eBooks have DRM. Since some eBook readers can't handle multiple DRM formats at the same time, it becomes important to be able to unlock the DRM'd book.
- Amazon Kindle doesn't support ePub format found in free, public libraries.
- Prebuilt Python Binaries for Windows.
- Barnes & Noble NOOK and NOOKcolor.
- Sony PRS-300 and the Sony PRS-350. This is actually a decent eBook reader, but I've been annoyed at Sony due to their PlayStation annoyances.
One immediate problem is that the NOOKcolor doesn't show the cover for sideloaded content that is downloaded through Overdrive. This is definitely a bug in the 1.1.0 firmware, since tweaking the epub file manually causes it to work.