When I was in my teenage years, I watched a lot of stand-up on Comedy Central. But now I don't really watch any, I'm not sure why I stopped. But I will say my favorite person on stand-up was George Carlin who had been doing it since the late 1950's. If you look up his earliest work, it's a little hard to recognize him except a much younger-sounding voice. While most people in their 60's and 70's usually have very little left in their career, Carlin was probably at his prime then. Especially as he was amazing at exposing the absurdity of religion, pointing out the stupidity of the "average" man, and correctly calling out corrupt politicians and their polices through his comedic wit.
Who's your favorite?