BackgroundTasks.cs

/*
    Subject / EventLoopScheduler / CompositeDisposable are all from the Reactive Library for .Net 3.5.
    Most of these classes are baked into .NET 4 AFAIK
*/

// Event loop and queue setup done in constructor
_sendQueue = new Subject<Action>();
var scheduler = new EventLoopScheduler( "EmailSender" );
var queueSubscription = _sendQueue.ObserveOn( scheduler ).Subscribe( action => action() );
_queueCleanup = new CompositeDisposable( queueSubscription, scheduler );

// Queueing a new task - just dumps an action on the queue
var sendDetails = new SendDetails {SurveyId = survey.Id, SenderId = sender.Id};
_sendQueue.OnNext( ()=> SendInvites( sendDetails ) );

// Cleanup the queue - encapsulating type implements IDisposable
_queueCleanup.Dispose();