object.GetBaseName(path) 

function ShowBaseName(filespec)
{
   var fso, s = "";
   fso = new ActiveXObject("Scripting.FileSystemObject");
   s += fso.GetBaseName(filespec);
   return(s);
}

Function GetTheBase(filespec)
   Dim fso
   Set fso = CreateObject("Scripting.FileSystemObject")
   GetTheBase = fso.GetBaseName(filespec)
End Function