/// <summary>
 /// Gets a list of all running Excel applications from the Running Object Table... in theory. In practise, due to Excel registering in the ROT with the same name every time,
 /// what you'll is x copies of the first Excel application, where x is the number of running Excel applications. This method remains just in case future versions of Office fix this
 /// issue, and because it could be useful to know how many instances of Excel are running. Each instance should be manually disposed.
 /// </summary>
 /// <returns>A list of Excel.Application objects</returns>
 public static IList <Application> GetRunningApplications()
 {
     return(Application.FromROT <Application>());
 }
 /// <summary>
 /// Retrieves all open Excel workbooks from the Running Object Table. Each instance must be manually disposed.
 /// </summary>
 /// <returns>A list of workbooks.</returns>
 public static IList <Workbook> GetAllOpen()
 {
     return(Application.FromROT <Workbook>());
 }