I always enjoy reading Siliconfile patents. It looks to me that the company has quite a few unusual, sometimes bright, ideas. The newly ublished application US20080290440 proposes to reduce the light reflection from silicon by using "concavo-convex surface" shaped surface. The picture below shows how exactly this reduces the reflection:
I'm not sure if this idea works for small pixels, where pixel size is of close to wavelength. Also, I believe the process of creating such a surface is not simple. But I like fresh, out of the box thinking of Siliconfile engineers.
Application US20080291309 by University of Pennsylvania in Philadelphia talks about pixel with amplifier transistor, instead of source follower. The application is written in a scientific paper style, with good comparison of different techniques and their strong and weak points. While I don't like their idea and especially their proposed implementation, it's a good educational read.