The book Cataloging the World - Paul Otlet and the Birth of the Information Age describes the work and vision of Paul Otlet - (one of) the first advocates for a world wide web.
Paul Otlet was also active for the creation of the first precursor of the United Nations.
The United Nations recently launched the Sustainable Development Goals - #SDGs in which a Mundaneum style utility would be very helpful.
Such a utility can now be co-created by all the willing, just by smart tagging their content when sharing it via social media. This page lists supporting tools.