You have to watch this TED video of a wearable sixth sense device. It consists of a portable projector, which projects on natural surfaces, and a webcam, both slung on your neck. These are pretty small, and do not seem to be very clunky. (They are off the shelf components). The demo shows some cool things like (a) the webcam identifying a plane ticket, and then projecting on the ticket, if the flight is delayed or if the gate has changed ; (b) the wearer making gestures to take photographs, and the cam taking photographs ; and then later on, the user projects these on the wall, and does cool things like resizing, organizing etc.