Alan Heller introduced me to his newest creation, the ErgoErgo seating concept, last month and I've been sitting on it every morning since. It does exactly what it says. By creating a dynamic seating situation, in which movement is constant and called for in balancing your "body moves slightly, keeping your core muscles engaged." It makes you slightly nervous at first, since you have to be awake and engaged and you can't slump in your task chair, but you get used to it fast, and it's very comfortable. It's also very affordable at $150 and chic enough to fit into an office, home office, or even work as outdoor seating (totally durable and waterproof). this is a great solution for folks looking for a good looking healthy seating alternative.