I was working similar idea, but for laws. They also change quite a lot and not very well presented online.<p>I halted the development after I realized how complicated can word diffs get. I would be interested about techniques that you used. I it is quite good as it is, but I noticed some common problems, such as:<p>1. Reusing letters from words that have nothing in common:<p>> fury over a [-hik-]{+n increas+}e in bus fares [1]<p>2. Inserting few paragraphs into one word (first paragraph) [2]<p>3. Loads of minor changes, also more of 1. [3]<p>[1] <a href="http://newsdiffs.org/diff/263401/263432/www.nytimes.com/2013/06/20/world/americas/brazil-protests.html" rel="nofollow">http://newsdiffs.org/diff/263401/263432/www.nytimes.com/2013...</a><p>[2] <a href="http://newsdiffs.org/diff/265812/265841/www.washingtonpost.com/world/asia_pacific/taliban-want-sign-on-their-qatar-office-resurrected-threaten-to-scuttle-talks/2013/06/22/ca979502-db0a-11e2-b418-9dfa095e125d_story.html" rel="nofollow">http://newsdiffs.org/diff/265812/265841/www.washingtonpost.c...</a><p>[3] <a href="http://newsdiffs.org/diff/265776/265810/www.nytimes.com/2013/06/23/world/asia/flooding-kills-hundreds-in-northern-india.html" rel="nofollow">http://newsdiffs.org/diff/265776/265810/www.nytimes.com/2013...</a>