Landlord: The Com Destroyer. A simple utility class to wrap those nasty little devils.

Landlord.cs

using System;
using System.Runtime.InteropServices;

namespace Things
{
    public static class LandLordExtensions
    {
        public static LandLord<TWrapped> AsDisposable<TWrapped>(this TWrapped tenant)
        {
            return new LandLord<TWrapped>(tenant);
        }
    }

    public class LandLord<TWrapped> : IDisposable
    {
        public TWrapped Tenant { get; private set; }
        private bool _disposed;

        public LandLord(TWrapped tenant)
        {
            _disposed = false;
            Tenant = tenant;
        }

        protected virtual void Evict(bool byManagement)
        {
            try
            {
                if (_disposed) return;

                if (byManagement)
                {
                    using (Tenant as IDisposable){}
                }

                if (Tenant != null && Marshal.IsComObject(Tenant))
                {
                    Marshal.ReleaseComObject(Tenant);
                    Tenant = default(TWrapped);
                }
            }
            finally
            {
                _disposed = true;
            }
        }

        public void Dispose()
        {
            Evict(byManagement: true);
            GC.SuppressFinalize(this);
        }

        ~LandLord()
        {
            Evict(byManagement: false);
        }
    }
}