Drupal is a free and open-source web content management framework.
Modernizr is a JavaScript library that detects the features available in a user's browser.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
ShareThis provides free engagement and growth tools (e.g., share buttons, follow buttons, and reaction buttons) for site owners.
Wufoo is an online form builder that creates forms including contact forms, online payments, online surveys and event registrations.