I've rarely heard of these "Hey, your hot. I want to take you out some time." encounters to work out. For a guy, if a gourgious women came up to them, he'd love to be asked out, and feels that a women would feel the same way if a guy asked them out on the spot.
Personally, I can rarely tell if this "chemistry" thing is there between us. My last few dates have been with gals who have asked for my number, or gave me their's. And that's how I know they like me
I haven't tryed it yet, but I can soooooo pull off a pick-up
Since it's more about confidence than looks, and I can do that for at least a minute