By seeding sheets of what look like paper with encrypted patterns of bacteria engineered to glow in certain conditions, researchers have developed an invisible ink for the biotech age.

Among the potential uses are secret, forgery-resistant bacterial barcodes and watermarks, though imagination soon arrives at more entertaining possibilities.

“Obviously, the secret agent kind of application jumps out,” said chemist David Walt of Tufts University, who developed the system with fellow Tufts chemist Manuel Palacios. “Somebody embedded in an environment where they need to get a message out but don’t w...

The Samsung Galaxy S II Epic 4G Touch, pictured, features a bright 4.52-inch Super AMOLED display. Photo: Jon Snyder/Wired

Samsung’s flagship smartphone, the Galaxy S II, has had a tremendously successful run with consumers since landing on U.S. shores, a prime example of Android’s continued success in the smartphone market at large.

Sales of the Samsung Galaxy S II have reached 10 million worldwide, doubling from 5 million sales in only eight weeks. The Galaxy S II first went on sale in the United States in late August, launching with versions for Sprint, AT&T and T-Mobile. The smartphone...