Available February/March next year. The “Lytro”:http://www.Lytro.com features a technology they call “light field” — they grab sufficient photon data at capture time to allow refocusing, zooming, etc as a post-capture option. The Lytro is a simple step on the way to a full software-defined lens — I first wondered about such a lens in 2003, should have filed a bunch of patents. Other people are pushing the idea ahead, see for instance “Software Defined Lensing”:http://www.creative-technology.net/CTECH/SDL.html.
As the writeup points out, you can view a traditional glass lens as a kind of quantum computer with a single fixed purpose, established at manufacture time. The lens captures all the incident photons, does some photonic/quantum computation, and spits an answer out on the CCD. But if we can replace the lens with something that has much more dynamic, programmable behaviour, well very cool things could be done — arbitrary refocusing and zooming being just the simplest example. A much broader set of incident radiation could be captured, spectral analysis of the image could be performed, filtering of the image, incredible levels of zoom, etc.
The Lytro is a very modest step in this direction but exciting.