It uses diafol's dwAPI class to retrieve a list of all forums, loops through them, and uses my Rss class to get the respective RSS feeds. It will show each forum in a separate div (with Dani's code) with it's title and no more than the five latest posts. The div will be omitted if there are no posts. (@Dani: some feeds give a parse error, and that's shown instead.)
You can try it yourself. Note that looping through all the forums takes some time, that's why the
set_time_limit(0) was included. If you want to see the result, look here.