Using A Microscope As A Hard Drive
An unnamed correspondent writes: "Nature reports that IBM Zurich is
developing a practical method for
braille hard disks that may eventually be able to pack 60Gbits per square inch, or about four times current disk technologies. I wonder how many moving parts there are with 1024 read heads." Well, they're not really braille; perhaps the analogy to clay tablets made in the article is closer.
The Sumerians developed cuniform hard drives in 5000 B.C. Not only were these portable (literally fit in the palm of the hand), but they could be read very well from many different angles. There was one write head (known as a "stylus"). Since some of these drives are still readable, they also hold the world record as the oldest surviving portable data storage system.