...make an animated application icon?

var
  icon1: Boolean;

  {....}

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  icon1 := not Icon1;
  case Icon1 of
    True: Application.icon  := Image1.Picture.Icon;
    False: Application.icon := Image2.Picture.Icon;
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  icon1 := True;
end;