Samus for awesome attitude, a creative arsenal, and sheer sex appeal. Heh.... She can use her Screw Attack on me any time she likes! *Shot repeatedly*
Other than her, I have a soft spot for many of the female Pokemon gym leaders, especially Winona, Whitney, Clair, and Sissy, and all four of the playable female characters in Tales of Symphonia.
Peach and Daisy are just plain boring imo.