Ya Richtig. I had one before they made one! It's about 5 euros, fits in your pocket, the pages are touch sensitive (you rub the page with a iPen or iPencil or iMydirtyfinger). It needs absolutely no battery. It accepts text inputs. You can flip through the 'pages' by swiping your finger from left to right, or from right to left. Totally intuitive interface.
An ink drawing of the Marie Theresa statue in front of the Kunsthistorische Museum, and a figure from a painting in the Kunsthistorische Museum (loved the hand pointing upwards to God, and how the shadow casts over the upper arm and torso).
Actually I'd love to have an iTouch and make electronic finger paintings (or even an iPad for the sake of its larger screen). See here for drawing examples. But for the meantime, my paper iPad does pretty good.