I came across a video of a digital art device called the I/O Brush. It has been around
for a year or two so you may have seen it, but thought I'd send just in case you haven't.
I am amazed by what can be done with it. It is essentially a camera brush that picks up color, texture and video that you can paint with on a special screen canvas. It is just unbelievable and I thought you would really like to see it.
There are video demonstrations towards the bottom of the page.