This should work. Go to
http://www.anonymizer.com/. From the top of the page you can type in the address of the site you want to go to (Yahoo, rotoworld, etc). The trick is that the request gets sent to the anonymizer site, they send the request to yahoo, yahoo sends back to the anonymizer, and eventually (nanoseconds later), the anonymizer sends back to you. So, from the corporate standpoint, it just looks like you're visiting anonymizer.com a lot. Depending on how closely you're monitored, you may or may not be able to get away with this for an extended period of time. They may become wise to your ways and add anonymizer to the blocked list, in which case you'll need a new plan of attack. Hope this helps, don't let the man get you down.