Here is a concept for a pair of sunglasses with a built-in video camera, that records everything you see.  This appeals to me; any number of times I’ve seen something particularly interesting or beautiful, and told myself, “if only I had a camera!”  (This is the same reason I want a camera phone.)  If the camera was built into the glasses, and always recording, I could always get back to those fleeting moments, those missing memories.  (link from Gizmodo.)