The Nook can read eReader PDB ebooks, see eReader content on the Nook
. The Jetbook Lite (reflective LCD screen) also supports it. Last time I heard, the original Jetbook did not support eReader PDB.
Alternatively, it is possible to strip the DRM (encryption) from the ebooks and, once DRM-free, they can be converted to MOBI (for Kindle) or ePub (for most other EInk devices) using Calibre. Apprentice Alf's Blog provides a good summary of the state of play in the DRM arena.