A:

unit Nosaver;

interface

uses
  SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
  Forms, Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
    procedure AppMessage(var msg: TMsg; var handled: boolean);
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.AppMessage(var msg: TMsg; var handled: boolean);
begin
  if (msg.message = wm_SysCommand) and (msg.wParam = sc_ScreenSave) then
    handled := true;  {TRUE = Disable the screensaver.}
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
  application.OnMessage := AppMessage;
end;

end.