Oh yeah? I bet I can make an overhead "slide" on the photocopier faster than your average professor can successfully scan in a figure from a book.

That's not what I mean. I'm talking about those little slides for slide projectors, the ones with big rotating cylinders. That's what artists used to (and sometimes still) do with their work to save a picture of it because you can project it to make it large rather than having a small photo of it. And that's what was generally used in art history classes. Plus, a digital image of it is more ecologically friendly than wasting a sheet of plastic.

And TEd, a digital camera image has depth, which distorts the text that would be on the board. Plus, the electronic white boards record directly to an image editing program and some of them even recognize handwriting, which can be directly inserted into a word processor document.