Economist and Red Bull
The Economist

This is a lovely site -- almost unexpected for the brand -- that demonstrates the diversity of its readership and tries to appeal to a broad audience in a (decent) attempt to expand its subscriber list.
I found this site inspirational, and it reinforced my decision to maintain my subscription to the newspaper. The only letdown is the poor audio quality of the voice recordings. The blogs offer a good opportunity to discuss and even offer links to other blogs that have taken the time to discuss the site -- including Piers Fawkes' PSFK site and the main Papervision3D blog site.
Red Bull Flight Lab

Red Bull is the answer to anyone who questions the online relevance of what is really only a fast-moving consumer goods product. You just have to use your imagination, identify who your audience is, and provide them with things they like. Red Bull does it better than anyone. I love this site even though I can't stand the taste of the product (too medicinal for my palette). But I am clearly in the minority.