The Ubersmith DE Device Manager allows you to determine which device entries are not currently associated with a client. From the Device Manager dashboard, you will see a link, 'Unassociated Devices'. Clicking this link will provide you with a list of all the devices within the Device Manager that do not currently have a client association.

This can help you tie up loose ends with respect to bandwidth billing, and also ensures that your clients have access to all the device information for the equipment they have in use.