How's this for a line:

"Excuse me, miss. You are entirely too hot and it's not fair to the other women. I'm going to have to ask you to leave.... With me."

Cheesy, but I think it's original, and it's gotta be better than "I must be in heaven, because I see an angel." I've never actually used a line on a girl unless you count my favorite from back in my Barnes and Noble days. It was so easy back then, jsut walk up to a pretty girl that's looking for a book, and ask her if she's need help. Then make some reccomendations, chat some more, impress her with my knowledge of whatever subject she is interested in (one of the good parts of being well rounded intellectually), then ask her if she'd like to get some coffee so we can continue discussing the best temperature to bake a blue glaze in. Other times I would walk up and say, "Excuse me, I think you're beautiful and was wondering if I could buy you a drink later?"