Sophos previously didn't have a full featured home-use antivirus.
They had one that you could run manually if you think you have an infection, and they had a home-use clause for their business customers that let them give it to employees for use at home for free, managed by the IT folks in the office, but there wasn't a way to buy it for home unless you wanted to buy the minimum size of 5 licenses for small business use.
Recently they made their UTM product (the firewall formerly known as Astaro Linux) available for free to home users and it comes with 10 licenses for home use for the full featured Endpoint Protection client.
The central configuration console on the UTM is not as slick as the Enterprise console, and it doesn't allow you to control Sophos' hard drive encryption software, but it does let you set up the Antivirus, Web Filtering, Firewall, and Intrusion Protection features. It doesn't need a Windows domain, so you can use it on Windows Home editions. The one thing that makes it really only for techie home users is that the UTM has to be installed on dedicated hardware or in a Virtual Machine.
If you already know how to set up a VM, then you are ready to go, just download the pre-built VM, or the software ISO and give it a try. http://www.sophos.com/en-us/products/free-tools/sophos-utm-home-edition.aspx
So with this you get a full featured Endpoint Protection program and a network based firewall system with more different VPN options than I have ever seen in one product. This is great for people running home labs for networking courses or Infosec research.
Having played around with it a bit at home I would rank it's UTM firewall capabilities fairly low in terms of flexibility compared to the FortiGate UTMs I'm familiar with, but you can't beat free for home networks.