Sorry I didn't respond sooner; I actually thought this went to the list, and since the topic has been discussed here at length, I hoped that someone would summarize. In short, you can just copy unprotected mp3 files to a card as you describe. The problem comes in when you work with protected content such as that from audible.com or rfbd. In those cases, the Book Port's serial number is required in order to encrypt the content. The battery drain is so minimal that a half hour transfer would not even really be noticed on a set a batteries. >>> hardy_graham@xxxxxxxxx Thursday, June 09, 2005 10:12:08 PM >>> Hello, I am a new member to this list. I have for some time now been trying to send this to Larry, though he never responded, which is, of course, very unprofessional of him. However, I suppose that there may be other APH staff on this list who may be more receptive. I recently acquired the Book Port, and like it very much in all respects but the following. When I send a large audio book to the Book Port, I find that it is very hard on the batteries, because it means that the device can be connected to the computer with an active serial connexion for sometimes a half-hour or longer. I do have another CompactFlash reader, and so, I suspect, do many other people who use the Book Port. I think that it would be nice if the transfer software could transfer a book to a device other than the Book Port. This would mean that, in stead of the files' being sent to the Book Port, the user would place the CF card into a conventional memory card reader, and the software would treat the contents of the card as if they were on the Book Port. In this way, a user would not have to waste so much battery power. Isn't this basically what the software already does? I am curious to hear your comments. Regards, Graham Hardy.