I have tried this routine once with some success, and wanted to see what you guys thought about it...

Assuming your sitting next to a cute girl who is not overly involved with work and seems open to conversation.

You open by saying, "don't you find it weird that people ask complete strangers to watch their stuff for them at coffee shops?" Her response doesn't matter really, it will probably be something along the lines of "i guess." Then you say, "no really think about it though if I was someone who wanted to steal something at a coffee shop and I had half a brain, I would go to the coffee shop with a book or laptop and look like any other guy and make sure I sat next to a girl (you could describe her if you want by saying whatever she's doing reading a book, working on a laptop etc.) because they always carry too much stuff, so they couldn't possibly bring everything with them when they have to get up to go to the bathroom...." and then you can kind of take it from there. if she is not giving you much to work with, you then simply say, "well i'll be here for a little while so if you need to go to the bathroom or anything I'd be happy to watch your stuff for you." Obviously, this routine has to be done in a way that's playful so she doesn't think your a creep who might actually steal her stuff.

And you can run variations of this if she asks you to watch her stuff before you get a chance to open with this. Or you can ask her to watch your stuff and when you return, run a similar routine.

Input is appreciated... thanks.

Nice opener! I have used a variant in clubs that goes something like: "Would you please watch my drink for a couple of minutes? Make sure this guy (while pointing discretely to some random dude) doesn't slip something in my glass..." usually gets them laughing... But for coffee shops yours is better suited...

I like both of these.

I used something similar to the first opener in the college cafeteria. A girl actually asked me to watch her stuff and I delivered the opener before she left. While she was gone, I drew a turtle on an index card and cut it out with an xacto knife. I left it inside her backpack such that the head was slightly poking out.

She noticed it about 10 minutes after she came back ..... that was a fun night.

Al