My website http://5000best.com/tools/ may be relevant. It lists mainly the most popular SaaS tools, but a few categories include widely used software components (non-free software only - no open source):

http://5000best.com/tools/Modules/

http://5000best.com/tools/Software_Dev/

http://5000best.com/tools/Specialized/

http://5000best.com/tools/Wordpress/

http://5000best.com/tools/Joomla/

http://5000best.com/tools/Drupal/

http://5000best.com/tools/Magento/

http://5000best.com/tools/E-commerce/