Save the attached generate_all_docs.php script into admin/xmldb/actions/generate_documentation on your moodle site (2.0 dev only), then visit the .../admin/xmldb/actions/generate_documentation/generate_all_docs.php URL in your browser.

You will find that this builds a set of HTML pages in moodledata/dbdocs/. These are entirely self-contained HTML files and can be copied anywhere else.

I suggest we set this up to run automatically once per day (or at the same time as the unmerged files check), and add the generated contents somewhere public. How about in a subdirectory on http://phpdocs.moodle.org/, with a link on that site's front page.