Simon Willison’s Weblog

TOSBack | The Terms-Of-Service Tracker. Fantastic idea (and implementation) from the EFF—a site that currently tracks 44 website policy documents and highlights changes to them using a diff engine (from Drupal). A global RSS feed is available—it would be useful if individual feeds for different sites and organisations were also provided. 7th June 2009, 10:49 am

Neil Fraser: Differential Synchronization. Paper describing a robust method for “keeping two or more copies of the same document synchronized with each other in real-time”, over a variable network connection using clever diff algorithms. 24th January 2009, 11:57 pm

google-diff-match-patch (via) Robust algorithms to perform the operations required for synchronizing plain text, in Java, JavaScript and Python. 9th June 2007, 6:15 pm

Feedwhip. Create an RSS feed or e-mail alert for changes made to any Web page. 27th May 2007, 8:43 pm