Piping All Feeds into Main Blog

I have a podcast theme that I love. We're upgrading to WPMS. What I'd like to do is take all of our network feeds and pipe them into the main blog as one feed.

I know that there are some indexer plugins here as well as "network themes", but I don't want to do this as a widget and the themes on WPMUDev are not built for podcasting.

Any thoughts as to how I can accomplish this?