Enter the Ganton Gym and spawn the Jetpack. Go over the arrow, out but do not go out. Fly up through a blank tile. An all-black area will appear. Use the thermal goggles to see all the people you have killed. You can also see an illegal tattoo parlor, a tornado, a hidden city in your garage in San Fierro, a tornadom and other things. Do not lose height or you will have to kill yourself when you land.