Long hair on men can be soooo sexy. Think Steve Perry. I can’t imagine how my parents would have reacted had I brought someone home who looked like him.
FWIW, I’m happily married to a stock broker, who would look absolutely ridiculous with long hair.
Aw, dammit!
OK, I’ll play, even though mine is a bit embarassing:
Mean girls.
Kind of stupid, mindlessly mean, superficial, not just confident but actively vain, vapid, hateful, spoiled.
These are qualities that ensure that I would never be interested in a person.
And yet my reptile brain insists that they are attractive qualities.
I don’t know why.
I am ashamed.
For me, it was always the “Campus Girl” look. Comprised as such:
[ol]
[li]Umbro soccer shorts[/li][li]Baseball cap with pony tail pulled THROUGH the back[/li][li]Rumpled sweatshirt[/li][li]Tennis shoes with short white socks[/li][/ol]
Not too surprisingly, I married a girl I met at a tennis drill. 
I second the Asian thing, as well as the Goth thing. Funny about the Goth thing, though…I don’t even know any Goth-ie women, much less was ever in a position to do something about it.
-Cem
In the spirit of the OP’s intention, I’ve always dug dudes who sport the “greaser” look. But I never had the courage to bring one home to meet Mom, and my wonderful fiancee is about as far away from this look as you can get.
Chain-smoking guys with tattoos, slicked-back hair, chain wallets…rowr