From there, it could become possible for the SIMs to communicate with rogue cell phone towers -- maybe 10 feet tall -- that could be set up in response to a humanitarian crisis like the Haiti earthquake or a communications blackout like those seen in Egypt, Libya or Syria. Those towers and the altered SIM cards could make it possible for small groups of people to communicate over a network, Gosier said.

"The technology is there," Gosier told me. "The problem has been the phones people have can't talk to the towers. So this open source software we're trying to build would allow you to essentially flash SIM cards and distribute them to people. ... At that point they could talk to whatever networks they want."

Until then, the Open Sim Kit could be used by activists to pass digital information to each other, often by hand. Sasha Kinney, who works with journalists and activists in Kenya as part of a group called Pawa254, said even that simple update "would definitely be something of interest" for journalists trying to evade government censorship.

"The more offline we can get and the more creative we can get the better it is for us," she said. "And everybody's got a cell phone here."

Election monitors in Kenya also plan to use SIM cards to record information about polling places and election-related violence, Gosier said. They'll pass them off to coordinators by hand, who then will take them to a place where the data can be uploaded to the Internet.

In a sense, that makes the SIM card a substitute for paper. But, unlike paper, SIM cards can be encrypted and stored discretely. They're less likely to catch the eyes of authorities.

"Think of it like passing around a thumb drive," he said.

A thumb drive that costs about 25-cents -- and doesn't require a computer.

Which is why the SIM card -- and other affordable, ubiquitous technologies -- is likely to make a comeback as a modern vehicle for free speech.

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