I was at SIGGraph recently, and I ran across the Origami Lens people, actually a graduate student from U.C. San Diego. The basic technology is the same as a Newtonian telescope, where parabolic mirrors are used to bend light rather than refraction through a lens. This technology uses a specially cut mirror on one side of a crystal lens, and a flat mirror on the other. The light enters the outside portion of the lens, gets reflected several times and enters the device from the center.
The quality is so much better than a standard small lens like one would find in a cell-phone camera. The weight and size is also drastically changed. While the lens has to be larger in diameter for a given f.stop (which depends on the area of the light coming through the lens), it can be much shallower and thinner.
This is the future for fixed focal length lenses. I'll be watching to see how they handle zoom lenses.