One of the great things about Google App Engine is, if you stay inside the box, so to speak, many things are a doddle. So much so that I was able to create this new app, Googomi, in a day or two, most of which involved fiddling with and learning about the Google+ API.
The Googomi app is a very simple beast with only one purpose: it will take your public Google+ stream and turn it into an RSS feed.
I've put a modicum of processing into it, so that it should correctly guess the most appropriate title for each RSS item, eg choosing the annotation, or the remote URL's title, where appropriate.
I personally had a use case for this (apart from learning about various Google APIs) whereby I wanted to export Google+ posts to other services automatically. For example, with this I can post from Google+ to Buffer and then beyond automatically.