Ask HN: Really awesome chair for computer use?

Curious if there is a known brand or some specific chairs for home/office use tailored for us hackers who desire a bit of extra comfort? I am talking about something like dentist chairs or something like this: http://videogames.techfresh.net/wp-content/uploads/2009/12/Emperor_1510.jpg , does anyone here use similar at home or in the office?