use Perl

1. a Wiki-ish Slashodot-ish solicitation of
   I'm looking at this, and it looks like that,
   and moderating up/down the submitted links by saliency.
2. Crawling CPAN, much like the current state of the art.
   1. Just mimic the file system on CPAN.
   2. Mine the source for use or require.
   3. Mine the docs for prerequisites;
   4. Mine the PODs for see also.

Some background reading:

Bates' Berrypicking metaphor, and more accessible "ontology" fallacy: reviewed.

A good analogy is to say that faceted
classification is to hierarchical classification
as relational databases are to hierarchical
databases. Most system designers would not dream
of using hierarchical files these days, so why
are hierarchical classifications of information
content still being used.

Ontology Development 101 at The Farm.
Most helpfully, The Semantic Web: Taxonomies vs. ontologies.

browse.cpan.org should be easier to invent than a system for
browsing underwater videos looking for schools of fish or for
inferring visual saliency by tracking eye movements [Nature.com, .PDF]

Or perhaps search by keyword is the dominant findability technique,
and browse related is for the birds.

philosophy of information : programmer -- ornithology : bird

ps I'm not affiliated with LinuxNow
( CPAN Listings: The Browse Feature is currently being upgraded.
Please use the search feature in the mean time.)