What you never explored the wonderful world of academia research papers and other whitepapers?
Here an interesting one
Coworker, An Inter Process Communication framework for AS3 Workers
This paper shows a multiprocessing framework in ActionScript3 on top of the official Worker API. It is used in the Visumag application.
You can download the PDF from there and in the references you will find URL for the sources etc.
the code is not super clean but it has the merits to be accompanied by a PDF document that explains it all and we can never have enough workers example