Initializing and setting DefaultCrendentials for OrganizationService in CRM 2011

I created a simple windows application just to see how to make use of IOrganizationService within CRM 2011.

Here we need to add references to the following dlls

1. Microsoft.Xrm.Sdk.
2. System.ServiceModel.
3. System.Runtime.Serialization.

This is the sample code

Uri organizationUri = new Uri("http://crmservername/orgname/XRMServices/2011/Organization.svc");
Uri homeRealmUri = null;
ClientCredentials credentials = new ClientCredentials();
// set default credentials for OrganizationService
credentials.Windows.ClientCredential = (NetworkCredential)CredentialCache.DefaultCredentials;
// or
credentials.Windows.ClientCredential = System.Net.CredentialCache.DefaultNetworkCredentials;
OrganizationServiceProxy orgProxy = new OrganizationServiceProxy(organizationUri, homeRealmUri, credentials, null);
IOrganizationService _service = (IOrganizationService)orgProxy;
try
{
    Entity myAccount = new Entity("account");
    myAccount["name"] = "Test Account";
    _service.Create(myAccount);
}
catch (Exception ex)
{
    MessageBox.Show(ex.Message);
}
}