Desk Chair Lust
My desk chair has finally succumbed to the sheer might of my ass. Hrm, let me rephrase that - the cushioning is completely lost on this thing, so I'm using pillows to maintain any sense of comfort. I have to face the fact that I need a new one.
While the likelihood of my getting any of these approaches nil as the economy approaches zero, I can covet from afar. Join me, won't you?

Herman Miller: Aeron. The desk chair that started a revolution. base price $842 CDN or so

Humanscale: Liberty. Slate thinks it's superior to the Aeron. $809 CDN base price
Steelcase: Think (3D-Knit). Orange! Coconut! $730 USD
Knoll: Life. Shiny. $922 CDN
Added: some other ideas after the jump.
So, the chairs in the post are obviously elite models. There are cheaper alternatives, of course.
Ebay has this model for just over $500, which is rated highly by its buyers:
Look, it has a giant metal contraption underneath the seat! I love giant metal contraptions.
This one has no rating on Amazon, but looks equally contraption-y. $329 is a great price. Need an American friend, tho.

And there are plenty of 'lesser' mesh-back chairs:
See lots of chairs in CDN prices at atwork and lots of high end stuff at Gabriel Ross
Right now I'm sitting on a giant pilates ball, figuring that it's gotta be better than that other thing. I just read a report that says the ball-as-chair doesn't actually engage any more muscles than sitting on a stool. go figure.
Taking a simple concept, and making it complicated (and removing the whole point):

I'm sitting on my Ikea couch, as I do not have a desk chair at home, with a laptop, I do not find a real need for one. There is a plastic Ikea kitchen chair at the desk, where I sit like once every couple of weeks.
On a different note, the Humanscale: Liberty looks *exactly* like the chairs we have at the ref desk...but, that can't be right...hmmmm
You're lucky, in a way, that you're happy with a laptop and a couch. I really do need a desk, and I prefer big ol' screen and a proper keyboard and mouse. I sit down on the couch and I end up watch TV or playing XBOX.
I'm not sure about this ball as a chair thing.