use Perl; – portal specializing in Perl news.
Comprehensive Perl Archive Network (CPAN)
Graph Viz – very cool package that manipulates pictures of graphs. Uses a textual representation that is trivial to manipulate in Perl.
bookpool.com – "Discount technical books." An alternative to amazon.com if you wish to support RMS's boycott.
Procmail – a cool tool useful for filtering incoming mail. Works great with Perl.
pm_groups archive – Perl Mongers group leader e-mail archive