We've (linewize.com) have built we've built an open-source cloud-managed layer 7 firewall which is free to use. We provide complete visibility over internet use on a per user, device and application basis through our subscription services, all the firewall and filtering goodness is free for anyone to use. If you're keen to have a look the install instructions are here: http://linewize.com/install. Keen to know what you think.