Turn off the main water supply;
Closing the valve on the main water supply will cut off water to the house. Although there will still be some water in the lines, the damage will be far less if there is a leak while you are gone.
Check your sump pump;
Rainwater can also be an issue if your sump pump fails while you are gone and a rainstorm comes. This could flood your basement. Dump a bucket of water in your sump crock and make sure it turns on and pumps the water out. Another good idea is to have a battery backup in case the power goes out during a rainstorm while you are gone.
Turn up the thermostat to save energy;
You can save on energy costs by turning up the thermostat while you are away. With programmable thermostats you can set the temp to 85 for example, and then have it go back to 72 when you return. Do not turn off the A/C or furnace while you are gone. This will help air circulate to avoid condensation.
Unplug electronics that are not protected;
If any electronics are plugged into the wall instead of a surge protector, unplug them. If they are plugged into a surge protector you can flip the switch to turn them off. This will also save on energy.
Light rooms with timers;
To make your house seem occupied you can set timers to turn on and off some lights in the house. This will make your house less appealing for burglars. Timers cost only about $10, a minimal cost to help protect your house.