Anyone have a good technique for when you're in an elevator?

I live in a hi rise and there's a lot of opportunity. Problem is, the elevator I typically have 20 seconds from when they come in to when we part.

My game isn't that fast. Usually all I can do is open them with a quick blurb. "Cool shirt! I like it. Do you actually like Spider-Man or are you a poser?" "Are you on your way to the gym? Today's an awesome day for running." Looks like you're about to have a party. "

But that's it. Maybe two statements and two replies.

Any tips on what to do? If I can get to a number and a date I'll call it a success.