Plans for homemade projectors are appearing around the web and our fatherless Jeep loving friends over at jeepbastard are providing a little insight to this homemade project. Essentially all plans work around the same concept, remove the backlight and reflective material from an LCD (monitor or laptop) and place it on top of an overhead projector. Some creative engineering is needed for proper mounting and cooling, but once it is complete people claim for it to display identical to the low end digital projectors. If people complain about how big and ugly it looks, simply throw some of the money you saved at them, that will shut anyone up in a hurry.
Homemade LCD Video Projector [Jeepbastard]