Types of Asynchronous Social Activity (initially in rough chronological order):
Asynchronous implies some kind of persistance is used. Can anyone think of other AsynchronousSocialActivity that doesn't require writing?
Yes, I have had extended "Answerphone Conversations" with my dad. We are both out a lot of the time and end up leaving questions/answers on each other's answerphones "Thanks! -- I added it!"
Tracking people and animals is a form of reading asynchronously the signs they left earlier. The sentences are much shorter, and you have to supply the words.
young buck stopped here, scratched antlers on tree two, maybe three coyote, ate a duck hereman, over 3' tall, of gnome class, walked with a limp, stopped muttered something about slaying dragons, turned and watched sunset then continued south along the beach
Grafitti is another form of asynchronous activity, so is littering.
Littering (and tracking) aren't social, but they are asynchronous. But I could be wrong; stalkers might consider tracking to be social.
I guess YouTube is another AsynchronousSocialActivity, that doesn't need written forms.
An AsynchronousSocialActivity, that doesn't need persistence will be communication with astronauts on their way to Mars.