Some of The Muppets videos went viral on YouTube in the past few years.
Other short form work also tends to go viral, YouTube is often credited with rejuvenating SNL, despite NBCs insistence on taking down every clip
People are brands too. I almost only watch talk show interviews in clip form.
However, the main way I've seen people do this so far is with viral content. Producing something that can go viral is very difficult for some brands - their culture does not support the risky, balls out attitude that does well online.
(If you have examples of viral content that does not fit this pattern then please let me know)