It depends on how close we are. If we get along extremely well and I really enjoy his company, I probably have thought about dating him. Personally, I want the person I date to be my best friend, so naturally being good friends with a guy makes him seem more dateable. If he's just an acquaintance, then there is a chance I might have thought about dating, but an equal one that he's "friendzoned" as well.
I think most people are friends with people they are attracted to on some level, but they don't match up enough for wanting a relationship with that person and the vibe just isn't there. I have hot female friends I've never wanted to date. When I first met them I wouldn't have been bothered by a nice make out session tho lol
It probably differs with each girl. I guess it happens relatively often with me as all 3 of the guys that I've dated in the past were initially my close friends before it turned to more. Including my current boyfriend.
If I think he's cute, then yes, because if we're friends then I already know we get along, I can trust him, he probably makes me laugh, etc. etc. But I have lots of guy friends who are think are wonderful great people, but I'm not attracted to them. So as always, it just depends on the guy. But yes, it's definitely not out of the question.