@schmurfy if you're not going to use Celluloid::Notifications (which, IMO, should work for this) at the very least it would probably be good to have an API that can register a proc to receive specific types of notifications. I'm wary of using the word "monitor" for this as Celluloid already has monitors (which are one-way links).

Perhaps something like this:

```ruby
Celluloid::Probe.on_event(:actor_created) do
  ...
end
```