Never comfortable for long periods of software development in a normal office chair I decided to modify a gaming chair.
All I've done is to replace the short plastic arms of an X rocker Jet gaming chair with much longer wooden arms.
The chair is made by www.xrocker.eu and has built in sound system too, but I hardly ever use that.
One of the photos contains details of the measurements that have worked for me with this particular chair. (A high-resolution photo is available from http://www.cyclestreets.net/location/36851/ .)
I have found that it is comfortable for long periods of work. I've used a cushion for a little extra back support, and its also quite good to put the feet up on a stool for even more laid back development.
Its a little bit of effort to get out of, because you're low on the floor and the shelf has to be picked up and then you must stand without putting too much weight on the long arms.
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