Actors: Object Orientation Evolved
gojko.net
gojko.net
Edit:
I found these, but I'm looking for something more concrete.
http://en.wikipedia.org/wiki/Actor_model
http://web.media.mit.edu/~lieber/Lieberary/OOP/Act-1/Concurr...
It looks more complicated than I'd feared. And Revactor hasn't been updated since 2009 and the docs say it's incomplete.