Ed Felten, and the various grad students who work for him at Princeton, have done plenty to contribute to the computer security field (and make quite a name for themselves), from breaking the old SDMI encryption that the recording industry insisted was unbeatable (which nearly got Felten sued) to showing just how vulnerable e-voting machines are. However, he may have just broken his biggest story yet. Felten and a group of colleagues have now shown that hard disk encryption is incredibly easy to beat. This should be a huge concern, considering how many people and organizations rely on data encryption to protect important data. In fact, with many of the "lost" hard drive stories over the past few years, many organizations have insisted the risk was minimal, since the data was all encrypted. Yet, as Felten's team shows in this video below, not only is it quite easy to defeat the encryption using a simple can of compressed air, in some cases, there isn't much that can be done to protect against this. As the video notes, this won't work on some systems if the computer is turned completely off and the encryption package opens up before the operating system boots -- but otherwise, most systems are vulnerable.
Basically, they've figured out that, despite what many believe, data held in RAM does not disappear immediately when the power is cut. And, if you freeze the chip, you can make the data last a very long time. This is important, because for disk encryption, the key to unlocking the data resides in the RAM. If someone can access that key in the RAM and make a copy of it, then they can unencrypt all of the data without knowing your password.