exercise ball as a chair?

I recently bought a Fit Disc and use it on my chair at work. It definitely makes me more aware of how I'm sitting.

Here's a link to the one I bought:
http://www.amazon.com/JFIT-20-1301-JFit-Disc-Blue/dp/B001181P8G

leangains.com

*uckarounditis most commonly manifests itself as an intense preoccupation with crunches, curls, cable movements, belts, gloves, balance boards, Swiss Balls and Tyler Durden. Fear of squats and deadlifts is another distinguishing trait. Physical exertion is either completely lacking or misapplied (towards questionable or unproductive training practices).

11. You're "training the core"...and it involves a Swiss Ball, Bosu Ball or something else that makes you look like an idiot.

"Training the core" is a phrase that is all too often used by people who are afraid to squat. You don't need special movements for the core, because it comes with the territory if you squat, deadlift, press and chin. No one squats 2 x body weight with a weak core.

We just had an incident at work where someone fell off their exercise ball/chair, whacked their head on the desk, and gave themselves a minor concussion. Now all ball/chairs are unauthorized. Good times.

Persuade someone to fall off their chair, see what happens then...