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Two hundred years ago, punching holes in cards was the hot new way to store data— in the weaving patterns of Joseph Jacquard’s automated loom. Now a new take on the idea has led to postage-stamp-sized chips that can store a terabit (1000 gigabits) of data, or the equivalent of 200 CDs. The system, known as Millipede, has been under development by researchers at IBM in Zurich, Switzerland, since the late 1990s (51¶¯Âþ, 27 March 1999, p 46). It uses miniature spikes that record data bits by making tiny holes in a plastic film coated onto a slice of silicon. To read data from the chip, the spikes are heated slightly and tapped onto the surface. If they hit a hole, they meet the silicon layer beneath, and the spike cools down. No temperature change means there’s no hole beneath the spike. Using the spikes to melt the polymer film erases data. IBM’s early prototypes could store 200 gigabits per square inch, but their new chips have boosted the data density fivefold.