I use a standard Office Depot leather desk chair. I think it cost around $180. It looks good, and more importantly it fits me like a glove. I actually went down to Office Depot and sat in all of their chairs that I thought looked nice, and then just picked the one that felt most comfortable to me.

I can sit in this chair 14 hours a day and never even notice it. I like that because I see my chair as being a productivity booster like using Zend Studio for php coding or Outlook for email. If I can sit comfortably all day (and all night, lol) I can really focus on what needs to be done.

If the Aeron Chair fits your body well go for it, but you can save a couple of bucks at a store like Office Max or Office Depot. They have the mesh chairs too, and you might find that one of these fits you much better than the Aeron.