i have a friend who used to come to our gigs to mix the board for us , on occasion hed bring his projector and laptop and run itunes or windows media visualiser through the projector onto the stage or wall and stuff it was pretty cool if the place was really dark and generally it was
digital projectors from what ive heard are pretty simple , computer ------projector and your pretty sweet , a white sheet is enough as long as the projector is in focus
i really would love afew of those analog projectors though , my drummer has an ols one with a 20watt tube amp in it hahaha its pretty cool . im thinking those wax and food dye in the petry dish things for an upcoming gig , real ungrateful dead acid test stuff ..chyeah