I just saw District 9 and thought it was pretty well done. Mike tossed up a good review of the movie here.
I was interested in other stuff the director has done and came across this link which collects ten of his short works (ads, shorts, etc.). They are worth watching. Except the last one. Skip that.
I knew about the Citroen commercial, Alive with Technology, long before the Transformers movie came out. I still that that one commercial is cooler than the Transformers movies. Check out the link: http://www.filmjunk.com/2009/05/04/the-short-works-of-neill-blomkamp/