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Trying to read an unwieldy newspaper on a crowded train is tricky—and
annoy your fellow passengers. But researchers at the Xerox Palo Alto Research
Center in California have the answer. They say a newspaper could be beamed by
radio to a 40-centimetre wide plastic rod called a “newsreader”. Inside the rod
is a coiled transparent rubber sheet coated with plastic. The sheet contains
millions of microscopic metal balls in oil-filled cavities, each ball coloured
half-black and half-white. Electric fields simply flip selected balls over so
that they look either white or black and display the words in response to…