Thought of it while reading one about asking for a good mens clothing store.

Walk up to the girl and say
"Hey I noticed you have a pretty good style, so i was wondering if you know where I can shop to get my mother something for mothers day?"

When you ask the question laugh and smile as if you were embarrassed to ask it while remaining confident. Used it in line at subway to a woman a few years older than me. Wasn't looking to close but just wanted to have a conversation with her to test it out.

This will only work until this sunday. But it can also be used anytime if you switch it and say "for my sisters birthday" or something.

How did she respond to this opener?

I like the fact that it begins with a compliment, and then transitions into a unique question. I would probably say something along the parameters of...

"Excuse me, I couldn't help but notice you have great style and I was wondering if you know any good places to do some Mother's Day shopping?" From there ask questions about what kind of merchandise they have, or what she thinks would make a great gift, or something like that.

You could rewrite this opener using any situation...

"Excuse me, I couldn't help but notice _______ and I was wondering if ________"

Women love fashion this should get her talking, and that is half the battle.

This vaguely reminds me of one of the day-game openers that "Style" recommends, which is to basically say the same thing about liking her style, and then to ask where around here you can shop for nice guy's clothes.