gistfile1.cs

public class Registrant
{
  private readonly List<Course> courseWishes = new List<Course>();
  public IEnumerable<Course> CourseWishes { get { return courseWishes; } }
  public string Name { get; private set; }

  public Registrant(string name)
  {
    Name = name;
  }

  public void WishForCourse(Course course)
  {
    if (!courseWishes.Contains(course))
      courseWishes.Add(course);
  }

public override bool Equals(object obj)
  {
    return 
      obj != null 
      && GetType() == obj.GetType() 
      && Name.Equals(((Registrant) obj).Name);
  }

// some hashcode implementation ....
}