This is too expensive for me, but I thought that anyone who was thinking of buying an adjustable astro observing chair might be interested in what I came across on ebay.
If I was going to spend that much I'd spend the extra and get a specialist obs chair from Bintel or such. I think they are about $180 and they are one of the best observing investments I've made. It's quite amazing how much extra detail you can see when you are comfortable.