Some chromedomes report they've figured out how to break the encryption used by CharlieCards and other "smart cards" that rely on wireless RFID connections to exchange information, such as account balances.
The trio say they are using their knowledge for Good, rather than Evil, by publicizing the possible flaw so that companies can do something about it before evil hackers start churning out zillions of counterfeit cards. One of the three is currently working on a PhD thesis titled Implementable Privacy for RFID Systems (that page also has a video of a talk on the issue).
Nohl and his colleagues "dissected" the MiFare chip to reveal each of the five layers of circuitry that make up the chip and produce the encryption. To do so, they looked at the chip under a conventional optical microscope, and used micro-polishing sandpaper to remove a few microns of material at a time to reveal each layer of circuitry, which then was digitally photographed.
Via Hiawatha Bray.