[Discworld] I would love to RP the Librarian. He'd wander into a game through the pathways of L-space, have some fun, rescue some books, hit some idiot calling him the M-word, and then head on out the same way.

And the only sign that he would have been there would be a sudden lack of bananas and a common caution among the residents toward any remaining apes.

that would be awesome

I wish I had the guts to play someone like Grany Weatherwax or Sam Vines

Either of them would be awesome.

They would, but I'm not sure most RP-ers can handle a character of the like interacting with theirs, to be honest

Granny Weatherwax in particular would be hard to RP, much less to RP with, I'd imagine.