This script will re-add the files of the selected tracks to iTunes as if they were a Podcast subscription. The files will then appear in the Podcasts playlist and "behave" as though they are a group of Podcast episodes. Such a Podcast can be set to automatically be copied to iPod and appear in the Podcasts category.
Requires "Web Sharing" be activated in System Preferences.
Mountain Lion Issues: Web Sharing activation is no longer available from the Sharing Preferences. See here for more information.