Delete all files with a particular extension in a particular folder and its sub directories

Delete files of a given extension within a directory and its sub directories e.g. to delete files with '.pyc' extension, use the following command:

find . -type f | grep '.pyc'$ | xargs rm

Varnish Cache

Recently I was tasked with installing and configuring Varnish cache for one of our websites. I went through alot of documentation on the internet and I would just love to post some of them here:

A Practical Guide to varnish
Speeding Up your website with Varnish
Magento with Varnish
Wordpress with Varnish
Varnish Documentation

Feel free to post others that I might have left out.