Hotties of the Tanach: Megila 15a

Our Rabbi's teach that the four most beautiful women were Sarah, Avigail (King David's wife, referred to as an ideal wife by the Mishnah), Rahav (a prostitute who saves Israel's spies during their conquest of Jericho), and Esther... Rabbi Issac said, 'Anyone who says "Rahav Rahav,' immediately ejaculates. Rav Nachman said to him, I once said, "Rahav Rahav" and nothing happened to me! Rabbi Issac replied, I was referring only to one who knew her and was acquainted with her.