This one is very situational to bars/partys, but Ive found creates a lot of interest. People love to hear about themselves.

You: You know a persons drink of choice really says a lot about them.
Her/Group: Yeah? What does *insert drink* say about me?

Then you either ask them to be more specific, or begin.

This one takes a little creativity/ preparation. I suggest getting a list from google to get you started and then adding your own bits and pieces to it. Also add some sort of backstory about something they may have done in their past, depending on your read of that person. Requires some thinking on your feet, but people seem to respond really well to this, especially when you nail the backstory.

What I'm unsure of is if I should list negative qualities or positive qualities or a bit of both. Unless of course they choose my drink of choice. For example, if they say "martini". Do I go with classy/sophisticated or high maintenance/pain in the ass?