Hi there I was surfing the other day and came across a cool Arduino controlled expresso maker http://www.youtube.com/watch?v=EepFpJpbJ6k&feature=related
But the cool thing I saw was the to be the next addon to the machine namly: http://www.youtube.com/watch?v=_6f00E-ge04
Where he guts a Cannon printer, puts edible ink in the printhead and uses Arduino + stepper to controll the forward, axis withe coffee mug on it.
So the question is How Hard Is It To do This?
I was looking into building a 3D- powder printer, so this would be a perfect start for such a project Printer spraying Water/binder onto Gypsum/printmaterial for one page and then lower the tray, rake new material over and start again.