Podcast Channels lets you setup 'Category-Casting' -- a different podcast per category.
All you need do is have the full URL of an audio file in a post, and it will pop up as an enclosure, and consequently in the RSS feed to be downloaded by a podcast client. So just use WP's usual uploader and Media Library -- a link to the file will do. Or if you use the wpaudioplayer plugin, the [audio: xxxx] text in the post will work so long as xxxx is a full URL to an audio file.
It seemed like a good idea at the time -- a way to setup more generic channels than just by category. You can put in PHP and WP's Conditional Tags here to make any kind of channel
is_tag('film') will make a channel in /tags/film/feed/
is_author('alan') will make a channel in /author/alan/feed/
Kind of cool, but not well tested. Let me know if you find this useful. You can specify full PHP code, and when it 'returns TRUE', the channel data appears in the feed.
If you don't use 'return' in the code, there is an implicit return added on the front and a terminating ';' on the end. If you DO specify return, remember to put the final semi-colon in.