Cool; though a few facts on your landing page might need some reconsideration. See e.g. https://news.ycombinator.com/item?id=36879311.

> something like a small computer of its own

Which corresponds pretty well with the Simula I concept, published 1966 in the Communications of the ACM. A Simula event notice (time, process) in the sequencing set is just a message step(process, time) in a priority mailbox; the two are the same mathematical object, making Simula's discrete-event active processes and Kay's message-passing active objects trivially isomorphic.