PerlLanguage patterns, especially GangOfFour DesignPatterns in Perl.

Take a look at ''PerlDesignPatterns'', a free online book and wiki: 
*** http://perldesignpatterns.com/?PerlDesignPatterns

On c2 Wiki:
* PerlSingleton

* Lists of sites:
*** http://www.google.com/search?q=%22patterns+in+perl%22
*** http://www.google.com/search?q=perl+design+patterns