SourceMaking — is the best information source on the Web on such software development topics as design patterns, refactoring and UML. A lot of information freely available through the site’s pages, so feel free to use bookmarklet to leave interesting chapters for further reading.
Render in Twig templates http://symfony.com/blog/new-in-symfony-2-2-the-new-fragment-sub-framework
Convert media files online from one format into another http://www.online-convert.com/
There are primarily two clients used with PHP. One is the older, more widespread pecl/memcache and the other is the newer, less used, more feature rich pecl/memcached. Both support the basics such as multiple servers, setting vaules, getting values, increment, decrement and getting stats. Here are some more advanced features and information.