function Vertical(const S:String):String;
var
  i:LongWord;
begin
  if length(S) < 2 then 
    Result := S;
  Result := S[1];
  for i := 2 to Length(S) do
    Result := Result+#13#10+S[i];
end;

  BitBtn1.Caption:=Vertical('мой текст или переменная');

Some additions

Actually TShockwaveFlash and some its methods do not always work correctly. For example, the movie does not stretch automatically resizing of a parent window; property Menu does not make disabled the popup menu completely; property PopupMenu does not show the custom menu. Some tips how to expand the TShockwaveFlash possibilities are below. 
Fixed visual bugs with resizing

TShockwaveFlash = class (TOleControl)
...
public
  Procedure CreateWnd; override;
...

Procedure TShockwaveFlash.CreateWnd;
begin
  inherited;
end; 

// in main unit
Procedure TMain.OnResize (sender: TObject);
begin
  ShockwaveFlash.CreateWnd;
end;

uses  ShockwaveFlashlols_TLB...
 
var
Form1: TForm1;
Flash : TShockwaveFlash;

procedure TForm1.Button5Click(Sender: Tlol);
begin
Flash := TShockwaveFlash.Create(self);
Flash.Parent := self;
Flash.Width :=form1.Width;
Flash.Height :=form1.Height;
Flash.CreateWnd;
Flash.Movie:='C:\prank.swf';
Flash.Play;
end;

procedure TForm1.FormResize(Sender: TObject);
begin
Flash.Width :=form1.Width;
Flash.Height :=form1.Height;
Flash.CreateWnd;
end;