Forum Moderators: phranque
I'm sure others will have some software suggestions and other solutions for you.
What I have to offer is a suggestion that your company implement a policy that forbids employees from accessing certain types of websites or other web services. That's because someone will almost always find a way around whatever blocking software you're using so you must have a solid policy in place to deal with it. Usually a few warnings followed by termination works well as an incentive for employees to avoid forbidden sites.
Also, it would be best to have a policy and buy the software that monitors website visitations. That way there are no filters, and people don't feel stifled. They clean up very quickly when they realize big brother is monitoring their every click.