Pretty much all the online openers I've received over the years have been lame, "Hey, what's up?" sort of lines.
But I remember back on my 25th birthday, I was single and sitting reading in some coffee shop like the loser I was, and some chick came up and said, "Are you from New Jersey?" I said, "No, why?" and she said, "Oh, you remind me of someone I used to know there."
Realizing quickly that this was an opener, I said, "Oh, that's interesting, care to have a seat?" and she accepted, sat down, and we dated for a month or so. I ended up dumping her because I wasn't that into her. (Probably why more women don't initiate with guys.)
So yeah that was almost 15 years ago and I totally remember it. Just goes to show how often I've been "picked up" by a girl in public. I can count on one hand the number of times in my life women have initiated conversations in a clear attempt to "open" me. I have no idea whether this is the norm or whether hotter guys get a ton of unsolicited come-ons.