For people who are looking for a low-cost way to watch video on a wall or ceiling, be on the lookout for a number of new pico projectors. One which was reviewed positively by Engadget is the WowWee Cinemin Swivel for iPods and iPhones. The price is low at $299 and the quality is not great. Moreover, this is not the only device of its kind.
Still, it is worth mentioning that this format may become a popular way to display TV in kid's rooms as it is low cost and they likely already have a portable music player or other compatible gadget already.