Another option: get a used LCD projector with a burned-out bulb. Put a very bright LED in there instead. I think I saw an Instructible on that. I've heard that some projectors get chucked out or sold very cheap because the replacement bulbs cost more than a new (and smaller and better and brighter) projector. Or, look out for a cheap LCD video display like the PS1, or a car seatback display, or a digital picture frame that has video input. Replace the backlight with an LED array, and add an enclosure and projection lens (magnifying glass, or maybe one scrounged from a scrapped overhead projector or slide projector).