Update: The index is defunct. It was only hosted on perlmonk.org, which now seems to be down for the count. Please disregard the below. My regrets to all.
It appears that the original PMSI simply listed the snippets ordered by different fields — title, author, date. Of those, the only one that seems remotely useful is ordering by title. If you want snippets by a given author, Super Search lets you find them; and ordering by date is practically useless. Hence, the following index, which orders only by title. (But also see Snippets Permuted Index.)
What people could really use is a catalog of snippets with value-added fields such as domain, complexity, quality. That would be a good collaborative project. ;-)