Anatoly Belychook uses “interprocess communication via data” pattern (see http://mainthing.ru/item/332/) - something like that:
One of the building blocks of Event Processing Network (EPN) presented in “Event processing in action” (see http://epthinking.blogspot.com/) is event processing agent. It can, in particular, aggregate many events from a stream. Use of such an agent (between pools, of course) looks like that:
I found it rather explicit. Maybe a next version of BPMN should consider some building blocks of EPN?