MIT researchers create a crash-proof file system
 

Nickolai Zeldovich and his colleagues at MIT have created a file system they claim is mathematically proven to be impervious to any unexpected system crash. The team built the file system on the basis of formal verification, which by itself isn't entirely new. What's different about the MIT team's work is that their formal proofs are made against the final code they wrote, and not against some high-level flowchart describing the system.

http://techreport.com/news/28898/mit...of-file-system