Sort of. I used to use a cheapo Wacom tablet with a painting app for online WebEx demos a few years ago; I'd flip from whatever thing I was demo'ing to a new desktop with a blank raster file open and draw explanatory diagrams. It was actually pretty decent. Having a pen integrated into the device, with some sort of transparent annotation overlay app would have been pretty exciting for me back then (not least because I wouldn't have to hand write text!).