[eschwartz]

I believe Sony/Kobo Desktop have ADE in them. That's basically it.

You do not need an account with Adobe, you can authenticate without an ID -- but then when you switch computers you lose the books. Also, you cannot sign into the same account on an reader if you don't HAVE an account. You need to login to the same account on all pcs/devices in order that they can decrypt the DRM. But once signed into the account, you simply copy the books over. The DRM is based off the ID used.