The new way to do a 404 Umbraco Handler

Hello all,
As you may or may not be aware I have been building a new Umbraco starter kit called CWS Start. In this package I wanted to have a 404 page setup for the site. Currently the way to setup a 404 page is to put a node ID in the umbracosettings.config file. My only concern with this approach is that if you delete the node and recreate the node then the 404 will stop working.

So I decided to ask the Umbraco community how they do 404’s and I got a fantastic response from the community.
http://our.umbraco.org/forum/developers/extending-umbraco/43866-Alternatives-to-404-in-umbracosettingsconfig

Stefan & Lee K gave me some fantastic answers and filled me on the new Request pipeline in Umbraco and a way on how to add a ContentFinder to Umbraco, aka the new way of doing 404 handlers in Umbraco 6.1 and any other type of content finders.

Show me the code!

    public class _404iLastChanceFinder : IContentFinder
    {
        public bool TryFindContent(PublishedContentRequest contentRequest)
        {
            //Check request is a 404
            if (contentRequest.Is404)
            {
                //Get the home node
                var home = contentRequest.RoutingContext.UmbracoContext.ContentCache.GetAtRoot().Single(x => x.DocumentTypeAlias == "CWS-Home");

                //Get the 404 node
                var notFoundNode = home.Children.Single(x => x.DocumentTypeAlias == "CWS-404");

                //Set Response Status to be HTTP 404
                contentRequest.SetResponseStatus(404, "404 Page Not Found");

                //Set the node to be the not found node
                contentRequest.PublishedContent = notFoundNode;
            }

            //Not sure about this line - copied from Lee K's GIST
            //https://gist.github.com/leekelleher/5966488
            return contentRequest.PublishedContent != null;
        }
    }

And then we need to register this in Umbraco on App Startup like so:

        protected override void ApplicationStarting(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
            //On application starting event...
            //Add to the ContentFinder resolver collection our custom 404 Content Finder resolver
            ContentLastChanceFinderResolver.Current.SetFinder(new _404iLastChanceFinder());
        }

There are other use cases for IContentFinders and Lee K has a great little example he posted to Gist