Автор: http://www.swissdelphicenter.ch

 // 4. Combined Delay 

{ 
  Including the Sleep in the loop prevents the app from hogging 
  100% of the CPU for doing practically nothing but running around the loop. 
}

 procedure PauseFunc(delay: DWORD);
 var
   lTicks: DWORD;
 begin
   lTicks := GetTickCount + delay;
   repeat
     Sleep(100);
     Application.ProcessMessages;
   until (lTicks <= GetTickCount) or Application.Terminated;
 end;