«His blackboard technique puts Rembrandt to shame.»
Purportedly taken from MIT’s Course Evaluation Guide
I was in a course in which the projector (more or less by accident) did project its image on a blackboard (“greenboard”?). At my suggestion, the presenter changed the background color to green and the text color to white. And hey, it did look nice:
And it can also be used to project complex images — as if you had drawn them on the blackboard:
And of course, you can use it to combine different input.