I think women like being complimented on their hair. They usually spend lots of time on it.
I tried it out once with a stripper in a strip joint and after I convinced her that I don’t have any hair fetishes she completely started blabbing away. Then I left. I just wanted to see if that sort of thing works.
Head hair only, as a first rule. (Although if you’re in the depilatory cream aisle – and might I ask why you’re there, exactly? – you could chance something a little more risqué…)
We should probably make this statement into a sticky for IMHO.
Walk by and “accidentally” drop the box of extra-large condoms near her feet. 
One day I was shopping and passed by a woman several times who looked exactly like Heather Locklear. We exchanged a glance, and smiled at each other, but I was WAY to shy to even attempt to speak.
When I got to the checkout, I saw her in line at one of the other registers. Something gave me the courage to roll my cart over and stand behind her. As the cashier was ringing her up, I somehow managed to utter:
“Eh, um…ah, excuse me, please don’t take this the wrong way, but did anyone ever tell you that you look just like Heather Locklear?” She looked up and smiled–
“Oh, thank you! I just hope no one thinks I’m a bitch like she plays on television!”
(untying tongue, gulping) “No–I don’t even watch her on TV–I just think she’s really a beautiful woman…” She flashes another smile, picks up her groceries, and starts to walk away. But then, she looks back, and says with another smile:
“Thank you, 'bye-bye.”
“Bye, Heather…”
End of story. I couldn’t think of anything else to say. My brain had stopped working. Pretty lame, huh?
As a woman who has been picked up in the grocery store, I can only tell you what worked on me. The guy that asked me out passed by me in one aisle and then caught up with me in the next and said, “Excuse me, but I just had to tell you how incredibly beautiful you are.” I thanked him and we chatted for a minute and then I wrote down my number on the back of a ticket stub from the opera I had been to the week before to give to him. He looked at it and said, “The opera? Wow, I’ve never met a woman who enjoys opera before.” Then he winked at me and went back to shopping.
When we ended up going out he was the most incredibly boring man on the face of the earth, so it didn’t go anywhere, but I say a genuine compliment can’t hurt and is certainly better than saying nothing at all.
Ergh, Hey You, not to pick on you or anything, but from me and every female I know you’d get a “Err… thanks” and when you left a “eeeeww!!! creeepy!!!” and a check to make sure you weren’t following me when I left. Now, “Er, excuse me, do you have any idea how to pick a watermelon?” or “Do you know anything about marinades?” or “Wow, I can never remember what cuts of meat are which!”, on the other hand, that doesn’t skeeve me out at all, and it’s a compliment. (I get that a lot more these days, I guess because I’m starting to look like somebody who might know the answer - in other words, it ain’t people trying to ask me out.)
You could take your cue from Ron Burgundy"
“I saw you from across the party (aisle) and I felt compelled to tell you something. You have an absolutely… breathtaking… hiney. I mean that thing’s good. I want to be friends with it! Do you know who I am? I don’t know how to put this but I’m kind of a big deal. People know me. I’m very important. I have many leather-bound books and my apartment smells of rich mahogany. … I wanna say something. I’m gonna put it out there; if you like it, you can take it, if you don’t, send it right back. I want to be on you. … Wait. Wait, wait, wait, wait, wait. I… I wanna be on you.”