If you’re curious to try out a Lytro camera that assimilates all depth-of-field information in an image and so can be focused at any point in the image, then this hack is for you (if you don’t want to shell out for a Lytro camera).
Instead of capturing all the image space information, the hack uses a short video clip focused through the depth of the image and then pulls out stills that can be clicked in a composite image to bring any part of the image into sharp focus. It’s a temporal version of Lytro’s spatial approach to DOF control. Clever stuff.