I holler "How YOU doin'?" Like Joey Tribbiani, with a little smirk and wink. IOW, like a d0uch3canoe.
Well, maybe more like "How you DOIN'?" Slightly less ... canoe-ey.
No, seriously, I do. Can't help it. I was raised in New York. It just pops out like a zit before prom. I'm lucky I have any female friends left. But they all know it's just a reflex, not flirting.