If the stranger happens to bring up a subject I'm interested in and familiar with, then look out!.....because I won't shut up about it....It usually drives them away unless I get selfcounsious earliy enough and abruptly end the conversation....which also makes things akward so they usually leave.
If i'm out to get a task done and I'm intereupted by someone, I'll show little interest, blank stare, maybe nod my head here and there.....throw in a little smile maybe.
Basically just humoring them so I can geton with my day. Some can tell I'm not interested and cut things short.
(Usually*) I'f I'm approched by 2 or more.....I try to avoid it completly. I can't follow anything being said because I'm always wondering what the other/others are doing.
* This past summer I was out on the bike, pulled into a restaurant that is a popular motorcyclist hangout so I could rest and take a few pictures.
While taking off my gear off, I see about 10 people ranging from ages 12 to 55 heading staight for me I turn to look behind me and see there is no one else around. I'm like OH NO!
So I prepare for invasion and just focus on the one guy who introduced himself.
Turns out he has the same bike I do and was just curious about my ownership experiences with it so far. We exchanged information about our experiences, then proceeded to go on and on about other stuff I can even remember because at that point I was very ready for the converdation to be over and everyone else to go away.
I think I handeled it OK
It was nice to be reminded that I'm human, but at the same time I could have very happily gone through the day without that experience.