Was the "ListIndexer" snippet included with the base install? I seem to remember that it was, and I thought I remembered a forum post about it, but I could only find a question I had, and some French I couldn’t read.
It was an Etomite snippet that let you build a list of links using multiple folders and their children as the content, and it let you sort by date or title, and it had a bunch of other flexible features. Mainly intended to build an index page. I have hacked at it to make a crude combination of that and NewsListing, but it’s nowhere near prime-time, and it’s loaded with hardcoded extras that I wanted for my site.
Anyway, that may be a place to start; look in your snippet collection to see if it’s there.