There have been a few times when I spotted a guy who I just somehow knew was "like me". On these occasions I actually approached and spoke to them and my hunch about them was right. This was before I knew about Asperger's. Anyway, I think there might be something like "gaydar" for aspie people, maybe we can just spot each other.
I married one of these guys, and tho he definately wasn't an Aspie, I think he might be somewhere on the continuim because he was very social, and he had language problems, but he was an absolute genius at math and engineering. He could look at a building and I could say, draw a cross section of that building cut at a 30 degree angle and he would draw it FREEHAND and I would measure it and it would be correct. Freaky!
Anyway, if you get the feeling that you spot someone like you, go ahead and approach them because if they are an aspie, they will understand and you can be very matter-of-fact with them; like: "hi, I noticed you and I think we might have some things in common. What's your name?" I've done that to aspies and they respond fine.
Also, wear the Passport so other aspies can spot you. Wear an orange band on your wrist.