>>553 CTRL+A

  public
    id:ATOM;
    procedure WMHotkey(var Msg:TWMHotkey);message WM_HOTKEY;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  id := GlobalAddAtom('HogeHogeHotkey');
  RegisterHotkey(Handle,id,MOD_CONTROL,Ord('A'));
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  UnregisterHotKey(Handle,id);
  GlobalDeleteAtom(id);
end;