Try a standing desk, much better for you if you work long hours on the computer:
Amazon.com : The Executive Stand Steady Standing Desk / Stand up Desk (Black) : Computer Monitor Stands : Office Products
I've been using it for 3+ years and it feels great to stand all day long and turn a sitting job into a standing one! It gives me more energy and mobility, and I even get to shake my ass to some good music while I work
