Hey Rix have you tried using a Public Proxy Server.
Alot of sites are blocked here at work as well being both a Catholic health and Government Organisation, but putting a public proxy server address in seems to do the trick for most stuff. Port 3128 is the only that works for me.
http://www.publicproxyservers.com/index.html Obviously there is stuff I still wouldn't look at, at work. But some of things that are blocked or logged are just ridiculous.