The Pi had me intrigued as to how capable it was in a small nginx cluster, and how well it would scale. To test this out, I set up 2 pi's running Raspbian, and installed nginx, php, php-fpm on it, and set it up to run drupal. 2 VM's were then set up, 1 for a web master, and 1 as a mysql server. The mysql server had more resources, both were running on my desktop in virtualbox. I then restored a copy of this site to each, (excluding the database), configured them to use the mysql database on the VM, and tested them. A bit of chasing missing packages, and it was up and running.