First off what does a opener mean: Explaining it in a logical way, yes i know..i know, finally someone does it.When people are talking in a social group or daydreaming alone, they are talking or thinking in a coherent way, but when you drop a incoherent, but interesting topic, they subconsciously want to jump in THAT topic. So you stop "the train of thought" and make a "new one" but this time you are driving it, get it?
NOTE: Always use a opener looking at eyes and smiling. WHY????...well you want to build comfort you do that by smiling (WHICH SEEKS APPROVAL) and SMILING (BUILDS COMFORT).
5 Openers:
1.Dollars are always so ugly or sometimes look brand new
like they were just taken out a box,....(wait for her Answer).....
...(IOD ANSWER) Why??? ....
2.I thought a beer belly was bullshit, till i saw this girl, OMG and she wasn't even pregnant!!
3.Excuse me...What is Love?
4.I Think monogamy is wrong (THIS MAKES THE WOMAN TALK)
5.Army People are so screwed, so unlucky i cant believe how much anger grows on society.
HOPE IT HELPS
Well the dollar opener, I used it with a cashier in a Mcdonalds we Pick up artist's, have nothing to loose and we are supposed to know "THAT WE HAVE NOTHING TO LOOSE". Its also actually true, some dollars are all destroyed and f'ed up but some dollars look brand new. 
If you ever read juggler's great book "how to be a pick up artist" I higly recommend it to you dude, well they are also known as flopsies !!