This document describes how to set up PC-BSD v1.5. This release is based upon FreeBSD 6.3 and uses KDE 3.5.8 as default desktop environment. Taken from the PC-BSD page: PC-BSD is a complete desktop operating system, which has been designed with the "casual" computer user in mind. It offers the stability and security that only a BSD-based operating system can bring, while as the same time providing a comfortable user experience, allowing you to get the most out of your computing time. With PC-BSD you can spend less time working to fix viruses or spyware and instead have the computer work for you.

http://www.howtoforge.com/the-perfect-desktop-pc-bsd-1.5