We were quite impressed by the look of this Herman Miller chair and the claims made as to its therapeutic properties.
From the product page:
Embody’s rotation points are within the seat and back, and the base of the back remains fixed relative to the seat; this encourages the body to move naturally into the most positive seated postures.
Whether you lean forward or recline, your lower back support remains constant–no adjustments needed; users of all sizes can easily assume and maintain a reclined position.
Embody encourages this most healthful posture for computer users; working recline reduces compression of the spine and slows fluid loss from discs; plus, your head stays in line with your computer display.
Your arms move unimpeded, adding comfort and encouraging additional air movement into the lungs to feed your brain.
The back is “alive,” adapting to the shape and movement of your spine; it automatically adjusts to your shifting positions and supports you through the full range of working postures.
No matter what your spinal curvature, this adjustment lets you achieve a neutral, balanced posture and stay aligned with your computer display.
Embody has no hard, rigid frames; edges flex so there is no pressure on your legs and arms.
Product page with more images: Embody Chairs
(hat tip: io9)