Ocultando/exibindo o cursor do mouse

//Inclua na seção uses: Windows
function MouseShowCursor(const Show: boolean): boolean;
var
I: integer;
begin
I := ShowCursor(LongBool(true));
if Show then begin
Result := I >= 0;
while I < 0 do begin
Result := ShowCursor(LongBool(true)) >= 0;
Inc(I);
end;
end else begin
Result := I < 0;
while I >= 0 do begin
Result := ShowCursor(LongBool(false)) < 0;
Dec(I);
end;
end;
end; // Exemplos de uso:

MouseShowCursor(false); { Oculta o cursor }
MouseShowCursor(true); { Exibe o cursor }