NewsDiffs, which was born out of the Knight Mozilla MIT hackathon in June 2012, is trying to solve the problem of archiving news in the constantly evolving world of online journalism.
It was recently added to the thousand sites archived by the Library of Congress.
The New York Times highlighted NewsDiffs in the public editor's column (which had previously discussed the difficulties of revisions in the digital age). The next New York Times public editor even joined us for a 2013 SXSW panel (slides available online)
The changes which have drawn the most attention are the addition of "on this issue" to a New York Times editorial about Obama after the PRISM disclosures, and the disappearance of beef stroganoff from the obituary of a rocket scientist.
If you are a developer, you can check out the Github repository.