I have a standing desk at work… because I’ve read that sitting for a long time is bad. Just how bad was never spelled out so well as in the infographic below from medical billing and coding. Unfortunately, my desk at work also has a tall chair, as you can see in the photo above. Having the desk and chair probably even each other out, I probably stand at my desk 40% of the time and sit the other 60%… whereas if I had a normal desk, I would be sitting 100% of the time, so not to shabby if you ask me.
From: Medical Billing And Coding | via: Lifehacker

I've been told that getting an exercise ball to sit on instead of a chair can help with this because you need to use your abdominals to balance. Also, you get the bonus of being able to bounce around like a boss!
The co-worker in the cubicle right next to mine uses an exercise ball and she digs it. Strengthens the core. Perhaps I could get a giant ball that I could sit on at my stand-up desk.