www.gaiam.com balance ball chair, i worked @ wendys for 3 years, and sprained my tailbone filled out an accident report and went to the dr..blah blah...best thing was that summer we went on a houseboat for a week and we swam a lot.
anyway, it makes the difference for me to be able to sit and get up, as opposed to sitting on a regular chair, and not being able to get up as easily. have used these chairs for years. they strengthen the core muscles as well, worst thing about that is when one has a friend over, and you get to laughing hard, its rather difficult to stay on the ball...
katz