There are devices that do that. Some quick googling for "keyboard laser projected" finds a couple of products. Actually I remember such keyboard projector from

There are devices that do that. Some quick googling for "keyboard laser projected" finds a couple of products. Actually I remember such keyboard projector from some 6 years ago or so on thinkgeek. I'm not sure how well they work though. However, I agree that this is a major problem. Personally, I think that on-screen-keyboards are a bloody mess. I can't stand the lack of proper tactile feedback (no, letting the whole thing vibrate doesn't count).