Warranty Void if Removed

Digital photo frames are cool, but are a terrible waste of power. A photo frame is only useful while someone's looking at it. What I need to do is make a digital photo frame with a small camera built in. Every second or so it wakes up, takes a photo and performs face detection on the image. If someone is looking at it, it stays on and displays a photo until the viewer looks away. 

An extension would be to extract the position and size of the face to guesstimate the viewer's position in 3D space. Then apply Johnny Lee style head tracking to display a window into a 3D  world beyond the screen. Would be great to look at your wall and have a window to a prehistoric world with dinosaurs wandering around, or something. Move closer to the "window" and you'd see more of the landscape. Walk past the window and your viewing cone would scan the virtual world appropriately. Of course it would only work for one viewer's perspective, but it would still be wicked cool.

There are plenty of other fun things to do with a camera/display combo - hall of mirrors, etc etc.

Hopefully you could save enough power to have a wall-dwelling wireless frame that only needed charging every week or two. If only I had time to try it!