I don't know of many female political cartoonists, but Ann Telnaes is an exceptional one. I like the way she combines her ascerbic wit with a bold and elegant style. Her site showcases more of her work.
And here's a great story about how Banksy, the utterly brilliant rogue British graffiti artist (sorry, admiration compels the profundity of adjectives) visited the wall Israel has constructed to segregate Palestine. Banksy was threatened by Israeli soldiers. He also received an unsual compliment from an elderly Palentinian gent, who told him he thought the artwork beautiful:
The artist thanked him, but the man replied. “We don’t want it to be beautiful. We hate this wall — go home.”