I discovered something interesting this week.  Here's the scenario. I have a windows service which houses a singleton object that has live camera statistics generated from our gate traffic camera here at the port.  What this service does is

1. Monitors a directory for file changes (camera images updated every minute)
2. Does some fuzzy image analysis on the image to get a live traffic “count”
3. Stores a copy of the image in a byte array

The singleton object is marshaled like so:

RemotingConfiguration.RegisterWellKnownServiceType(typeof(VIT.Common.Classes.GateStatusRemotable), "GateStatus", WellKnownObjectMode.Singleton);

RemotingServices.Marshal(m_GateStatus, "GateStatus");

Now, I have need to remote to this object from two places, a windows application that acts as a service controller, and a web control that actually consumes the images and data, and publishes it on the web. 

Everything worked great, except that I found that the singleton object would disappear if I didn't access it!  Yikes!  Well, it turns out that the solution was simple.  MarshalByRefObjects contain a method called InitializeLifetimeService.  You can overload this to control the lifetime of your remotable objects.  To make my object live forever, I overloaded this method and returned null.  Works perfectly!  Here's the code.

public class GateStatusRemotable : MarshalByRefObject
{
 public GateStatusCollection GateStatus;

 public override Object InitializeLifetimeService()
 {
  return null;
 }
}

You can also return an ILease object if you want to get fancy with this.