Messaging/Eventing Framework

I am looking for a messaging/eventing framework that will allow changes in one application to be subscribed to by other applications. My situation is I have an ASP.NET web application that allows users to perform CRUD operations. I also have multiple unknown applications that are used to synchronize data in our application with data in a clients application. What I would like to do is allow our A开发者_StackOverflow社区SP.NET app to send out a notification that Company A has been created. I would like the client application to be able to "subscribe" to the event from our application. I basically want to get away from the need to modify our ASP.NET code each time a new client app is needed. What sort of technologies exist to handle this sort of situation?

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Check out NServiceBus: www.nservicebus.com

Excellent framework for handling communication between different business services.