BBC Javascript London 2012 Social Plugin
This funky project was to allow the user to 'favourite' an olympic category, say Team GB or Archery. This would then be saved, either via the BBC Id if logged in or through cookies/html storage if anonymous. Once saved, related content would be served up to the user in the form of a content tray. Up to five categories could be favourited.
This is harcore OO javascript with hardly any DOM manipulation. It also uses require.js.
The UI functions or in the favourite modules. The data API in the personalisation modules.