A podcast is just an RSS feed with a file enclosure – part of the RSS standard – that points to an MP3 file. Similarly, video podcasts point to video files. An obvious evolution, then, is the pubcast: periodical publications delivered through RSS feeds.
Free publication subscriptions
In the free case, a user would simply subscribe to a public pubcast feed with a compatible reader. The reader software would check regularly for updates, and new publications would be downloaded and fed into the user’s ereader software on release. Easy.
Paid publication subscriptions
In the case of paid publications, there are two options:
An authenticated pubcast feed. When you subscribe to a publication, you get an address to an RSS feed that requires a username and password to download content. (Gmail is an example of an application which already does this.) This authentication ensures that only paid subscribers can access the file, but you could go a step further and watermark the publications themselves.
Activation within the ebook file. The RSS feed itself is public, but each downloaded publication could require an access code to read. This would open the door for public feeds of paid journals, where users could buy each issue individually to read.
Making subscriptions an open standard
Either way, this approach would allow any ereader using any compatible software solution to subscribe to periodicals. It could be used for newspapers, magazines, journals, zines, or new kinds of periodical; they could be hosted anywhere and, in the case of paid content, use any payment provider. I love reading, but dislike monopolies, so this is something I’d like to see.