I was listening to Marc Maron interview John Oliver on his WTF podcast last night (highly recommended, BTW: Maron's interviews of comedians old and new are Parkinson-esque in their openness and insights), and they were talking about the fact that John Oliver is famous, but not well known as a 'named' celebrity.
It got me wondering about what makes comedians famous. Usually their fame is spread by recommendation, rather than direct advertising, at least until they are famous. So my question is: is it better to have a really good joke that people can share with their friends (and hopefully still attribute it to you), or to have a joke that only you can tell (because of the voice or the visual style)? The former has more memetic power but risks losing the attribution, whereas the latter won't spread as well, at least in principle.
Yet, both benefit from the modern media: YouTube spreads the unique gag, while the originator of the joke meme can be traced through the Internet. So, clearly, the ideal is both: a joke that is easy to re-tell, yet best served from source. The best combinations I've seen have been well-crafted jokes with some serendipitous interruption that has stamped the telling of the joke as unique: a heckle, a technical fault etc.
None readily spring to mind, but I bet there is (or should be) a website out there that collects such jokes. As I think of them or find them, I'll add them to the comments.