Watching the first two episode of Girls with the passive attention it deserved, I decided my favourite in the show was Zosia Mamet. I knew I had seen her before, but it never occurred to me she plays Peggy's lesbian friend in Mad Men, a show I watch religiously.
Here is some more Zosia Mamet from Funny or Die. Posted here with permission.
By the way, "Zosia as a girl's name is a variant of Sophia (Greek), and the meaning of Zosia is "wisdom". Speaking of wisdom, her dad David Mamet wrote Glengarry Glen Ross (the play and the movie) and Wag the Dog!