I think a signal or sign of some kind would be great when in public, that way we know who is looking too. How about we hook our thumb in our jeans pocket? I'm going to give this a try and see if anyone picks up on it.
I think that's a great idea. I'll be looking for it and I'll be walking about with my thumb in my jeans as well !
The way I see it, if it's a sign for bi guys but not obvious it's some kind of sign, only bi guys will read it and straights will just think it's a mannerism and you won't be outed in the process. The problem with finding one is the limited number of bi guys in here and if you go to some LBGT super group, it'll become common knowledge quickly. For example, the gay community has a signal with a handkerchief or bandana showing in the back pocket to indicate whether the guy is top or bottom by which pocket it is. That's something the whole world knows about. Let's keep thinking on it.