Le building
I recently came across this very funny animated short, titled Le building, done by some obviously very talented students at a school in France. It is done both with traditional and CG animation techniques, and the integration is truly exceptional. There is also a very good making-of video of Le building, worth looking at if you are interested in animation.
Many thanks to Drawn! for showcasing it (that is where I first saw it). If you like illustration/animation make sure to have a look around and bookmark the website.