I don't post here very often but I do read this and many other forums from work all the time. My work has filters that block access to certain sites that they don't want people visiting, and I figure anything else is fair game as long as I get my work done.

I don't feel guilty about browsing the web from work because I'm very good at what I do, I get it done on time, and I don't let browsing the web interfere with it.