I've tried this one when I was riding on a train with my friend, we were sitting next to 4 girls, we were talking our own stuff, they were talking their stuff and when we ran out, we listened to them (they were talking so loud that you could have concrete in your ears and you would still herad them
) and they were talking about some topic, that made me or him to remember something similar on the same topic form our lives, we talked about that, sharing stories, laughing and when we looked at them, they were laughing at the stuff that we told, but probably not from the stories, but cause we stoled their thread. 
We didn't talk or anything, but there was a ton of subconcious communication (body language, IOIs ...)
I was thinking, could I used this as a tool for game or is it for scraps, cause I only used it one time, so it's not really super tested
If anyone is going to try this or has some results, post it
Peace K.