I'm not really into anorexic skeleton type models or celebrities, but I'll try to pick one for the question... =P
How about Rachel McAdams as a brunette like in Wedding Crashers or Sherlock Holmes. She's got the energy that only a Scorpio can possess. The eyes and expressions say playful and cute, but sexy and naughty at the same time. Something I can relate to. =P
As far as fit an unattractive... Pick a random tennis player... Victoria Azarenka is number one at the moment. She's not attractive to me.