i would agree with Jbennet, you should not break the rules theer must be a good reason why they blocked, why don't you do it on your free time instead, no harm done. better to be safe than sorry. right?
you should use vpn service, it bind to the account not to the static adress. what it does it create a virtual network for you so you can access sites, applications, torrents that was blocked from the mapping routers of your providers. check on google for reviews of different vpn service providers, for instance may have a look here SNIPPETY SNIP SNIP SNIP, have fun. and yeah it's absolute legal !
Because a website is blocked doesn't mean it's breaking an IT policy, But by using a Proxy to avoid filtering is a violation of Policy, look carefully i can imagine 9 times out of 10 it will state that "The use of proxy or ways to evade filtering is prohibited and can be subject to disciplinary actions" Your best bet is to just go to the Technician and ask if he/she can unblock that specific site.