The Amazon Kindle and the Sony Reader Digital Book may be the first widely-accepted digital readers, but electronic ink technology holds more promise than just these two devices.

Imagine a magazine that updates its articles whenever new information is available. A tablet that stores all the textbooks a university student will ever need. Or a supermarket shelf tag that automatically reflects price changes. ZDNet correspondent Sumi Das shows us how electronic ink is turning the page on a new era for displays.