The event aggregator in Prism is great, and allows loosely coupled communication between modules within a composite application. Does such a thing exist that allows the same thing to happen between standalone applications running on a user's desktop?
I could imagine developing a solution that uses WCF with TCP binding and running inside Windows Process Activation Service. Client applications could subscribe or publish events to this service as required and it would ensure all other listeners get notified of events as appropriate. Using TCP would enable event messages to be pushed out to clients without the need for polling, ensuring messages are delivered very quickly.
I can't help but think though that such a thing would already exist... Is anyone aware of something like this, or have any advice on how it may be best implemented?