Global Author Posts Feed grabs all the posts from a single author, from across an entire Multisite or BuddyPress network, and puts them in a single feed.
A feed just for a selected author that combines all their posts into one big RSS job.
Completely Automated Setup
It’s really straightforward. No pesky options to worry about. Once it’s installed, simply click the Feed link next to the user’s name under Users > All Users in your network admin to open that user’s feed in a new window.
How Will You Use It?
Here’s some examples:
Use a theme that pulls RSS feeds onto it’s homepage
Add it to a 3rd Party RSS feed widget in the side bar
Let readers subscribe to it using a feed reader