All those little hoses and lines -- in the kitchen, bathroom, or utility room-that bring water to your sinks, toilet, and washing machine are also potential causes of floods in the rooms they serve. They create a messy problem if they break while you're at home. They spell disaster if you're out for the day and a catastrophe if you're gone for weeks or months.
Turn off the water supply valves to each water-fueled fixture in the home. This provides iron-clad flood insurance (at least for these items) for as long as you intend to be away -- up to and including a yearlong around-the-world cruise. Why not simply turn off the main water shutoff valve? Simple -- because the water supply to most landscape irrigation systems is controlled by the same valve, you would return from your extending trip to find your garden transformed into desolate surroundings.
Also, open a faucet and let it drip ever so slowly. This isn't the best suggestion when it comes to conserving water, but can save thousands of gallons in the long run by preventing a burst water line from freezing conditions.