Here is another chair that helps you stay a bit more active at work. The ENOVI Starfish Ball Chair engages your core and leg muscles as you sit on it. It encourages proper sitting posture. The ENOVI Starfish Classic Chair has a gym grade yoga ball and CFS steel frame to handle up to 600lbs of weight.
You can order this chair in 5 gorgeous colors. It has a machine washable slipcover.