diff --git a/NzbDrone.Common/Eventing/EventAggregator.cs b/NzbDrone.Common/Eventing/EventAggregator.cs
new file mode 100644
index 000000000..bb76f8479
--- /dev/null
+++ b/NzbDrone.Common/Eventing/EventAggregator.cs
@@ -0,0 +1,174 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+
+//From http://caliburnmicro.codeplex.com/
+
+namespace NzbDrone.Common.Eventing
+{
+ ///
+ /// Enables loosely-coupled publication of and subscription to events.
+ ///
+ public class EventAggregator : IEventAggregator
+ {
+ readonly List handlers = new List();
+
+ ///
+ /// The default thread marshaller used for publication;
+ ///
+ public static Action DefaultPublicationThreadMarshaller = action => action();
+
+ ///
+ /// Processing of handler results on publication thread.
+ ///
+ public static Action HandlerResultProcessing = (target, result) => { };
+
+ ///
+ /// Initializes a new instance of the class.
+ ///
+ public EventAggregator()
+ {
+ PublicationThreadMarshaller = DefaultPublicationThreadMarshaller;
+ }
+
+ ///
+ /// Gets or sets the default publication thread marshaller.
+ ///
+ ///
+ /// The default publication thread marshaller.
+ ///
+ public Action PublicationThreadMarshaller { get; set; }
+
+ ///
+ /// Subscribes an instance to all events declared through implementations of
+ ///
+ /// The instance to subscribe for event publication.
+ public virtual void Subscribe(object instance)
+ {
+ lock (handlers)
+ {
+ if (handlers.Any(x => x.Matches(instance)))
+ {
+ return;
+ }
+
+ handlers.Add(new Handler(instance));
+ }
+ }
+
+ ///
+ /// Unsubscribes the instance from all events.
+ ///
+ /// The instance to unsubscribe.
+ public virtual void Unsubscribe(object instance)
+ {
+ lock (handlers)
+ {
+ var found = handlers.FirstOrDefault(x => x.Matches(instance));
+
+ if (found != null)
+ {
+ handlers.Remove(found);
+ }
+ }
+ }
+
+ ///
+ /// Publishes a message.
+ ///
+ /// The message instance.
+ ///
+ /// Does not marshall the the publication to any special thread by default.
+ ///
+ public virtual void Publish(object message)
+ {
+ Publish(message, PublicationThreadMarshaller);
+ }
+
+ ///
+ /// Publishes a message.
+ ///
+ /// The message instance.
+ /// Allows the publisher to provide a custom thread marshaller for the message publication.
+ public virtual void Publish(object message, Action marshal)
+ {
+ Handler[] toNotify;
+ lock (handlers)
+ {
+ toNotify = handlers.ToArray();
+ }
+
+ marshal(() =>
+ {
+ var messageType = message.GetType();
+
+ var dead = toNotify
+ .Where(handler => !handler.Handle(messageType, message))
+ .ToList();
+
+ if (dead.Any())
+ {
+ lock (handlers)
+ {
+ foreach (var item in dead)
+ {
+ handlers.Remove(item);
+ }
+ }
+ }
+ });
+ }
+
+
+ class Handler
+ {
+ readonly WeakReference reference;
+ readonly Dictionary supportedHandlers = new Dictionary();
+
+ public Handler(object handler)
+ {
+ reference = new WeakReference(handler);
+
+ var interfaces = handler.GetType().GetInterfaces()
+ .Where(x => typeof(IHandle).IsAssignableFrom(x) && x.IsGenericType);
+
+ foreach (var @interface in interfaces)
+ {
+ var type = @interface.GetGenericArguments()[0];
+ var method = @interface.GetMethod("Handle");
+ supportedHandlers[type] = method;
+ }
+ }
+
+ public bool Matches(object instance)
+ {
+ return reference.Target == instance;
+ }
+
+ public bool Handle(Type messageType, object message)
+ {
+ var target = reference.Target;
+ if (target == null)
+ {
+ return false;
+ }
+
+ foreach (var pair in supportedHandlers)
+ {
+ if (pair.Key.IsAssignableFrom(messageType))
+ {
+ var result = pair.Value.Invoke(target, new[] { message });
+ if (result != null)
+ {
+ HandlerResultProcessing(target, result);
+ }
+ return true;
+ }
+ }
+
+ return true;
+ }
+ }
+ }
+}
\ No newline at end of file
diff --git a/NzbDrone.Common/Eventing/IEventAggregator.cs b/NzbDrone.Common/Eventing/IEventAggregator.cs
new file mode 100644
index 000000000..369b8a8f1
--- /dev/null
+++ b/NzbDrone.Common/Eventing/IEventAggregator.cs
@@ -0,0 +1,47 @@
+using System;
+using System.Linq;
+
+namespace NzbDrone.Common.Eventing
+{
+ ///
+ /// Enables loosely-coupled publication of and subscription to events.
+ ///
+ public interface IEventAggregator
+ {
+ ///
+ /// Gets or sets the default publication thread marshaller.
+ ///
+ ///
+ /// The default publication thread marshaller.
+ ///
+ Action PublicationThreadMarshaller { get; set; }
+
+ ///
+ /// Subscribes an instance to all events declared through implementations of
+ ///
+ /// The instance to subscribe for event publication.
+ void Subscribe(object instance);
+
+ ///
+ /// Unsubscribes the instance from all events.
+ ///
+ /// The instance to unsubscribe.
+ void Unsubscribe(object instance);
+
+ ///
+ /// Publishes a message.
+ ///
+ /// The message instance.
+ ///
+ /// Uses the default thread marshaller during publication.
+ ///
+ void Publish(object message);
+
+ ///
+ /// Publishes a message.
+ ///
+ /// The message instance.
+ /// Allows the publisher to provide a custom thread marshaller for the message publication.
+ void Publish(object message, Action marshal);
+ }
+}
\ No newline at end of file
diff --git a/NzbDrone.Common/Eventing/IHandle.cs b/NzbDrone.Common/Eventing/IHandle.cs
new file mode 100644
index 000000000..afbf70fae
--- /dev/null
+++ b/NzbDrone.Common/Eventing/IHandle.cs
@@ -0,0 +1,22 @@
+using System.Linq;
+
+namespace NzbDrone.Common.Eventing
+{
+ ///
+ /// Denotes a class which can handle a particular type of message.
+ ///
+ /// The type of message to handle.
+ public interface IHandle : IHandle
+ {
+ ///
+ /// Handles the message.
+ ///
+ /// The message.
+ void Handle(TMessage message);
+ }
+
+ ///
+ /// A marker interface for classes that subscribe to messages.
+ ///
+ public interface IHandle { }
+}
\ No newline at end of file
diff --git a/NzbDrone.Common/NzbDrone.Common.csproj b/NzbDrone.Common/NzbDrone.Common.csproj
index db9143e3c..2f450d59c 100644
--- a/NzbDrone.Common/NzbDrone.Common.csproj
+++ b/NzbDrone.Common/NzbDrone.Common.csproj
@@ -110,6 +110,9 @@
+
+
+