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Two technologies may revolutionize ink-on-paper printing, electronic ink and electronic paper. 

Electronic Ink

Tiny capsules contain a liquid blue dye and  negatively charged white pigments. The 100 micron wide capsules are suspended in a liquid carrier which can be used to transfer them to a substrate producing a density of 256 capsules (dots) per inch. When placed between charged electrodes, the pigments migrate within the capsule. A negative charge will attract the white pigments to produce a white image, and a positive charges will produce a blue image. Charges can be applied either from the viewed or hidden side of the substrate, or both. When the power source is removed, the capsules will remain in position for weeks. To image the are of a mousepad, 0.1 watts are required. Reapplying a charge will redistribute the pigments to form different images, like tomorrow's news. 

Electronic Paper 

A similar idea is an 'electronic paper' consisting of two transparent layers containing an oil with suspended beads. The beads have different colored hemispheres charged positively and negatively. When a charge is applied to the sandwich, the beads rotate to expose the desired hemisphere, either completely to produce a single color, or partially to expose a portion of each color. In this manner, a grayscale or vignette can be produced. Once rotated, the beads maintain their position until a subsequent charge is applied.