Actually I believe the best pickup line is a genuine sincere smile and a warm "hello". If a person finds you attractive things are off and running. Pickup lines are nothing more than "ice breakers".
However if one just wants to try to elicit a laugh or go down in flames there are numerous pickup lines one can use to "break the ice".
All pickup lines should be done with a smile or raised eyebrow.
"I'm no Fred Flintstone but I bet I can make your bed rock!"
"You must be tired because you've been running through my mind all day long!"
"Did it hurt when you fell from heaven?"
"If being beautiful were a crime you'd be on death row!"
"They say love is blind. Allow me to introduce myself, I'm Stevie Wonder."
"I don't normally approach strange women but if I didn't talk to you my friend would. You can thank me later"
"My friend bet me $20 you wouldn't go out with me. Lets take his money and enjoy a cocktail or cup of coffee somewhere."
"Can I have my heart back?"
"Do you believe in love at first sight? or Do you need me to walk by again?!"