Cats are great pets to have when it comes to vacation time.  You could probably go away for at least a week and not even require any kind of sitter or caregiver as long as you put out enough bowls of food, water, and several litter boxes. 

When we got home from our Cozumel trip, none of the cats got up off of their butts to greet us when we got home at midnight.  My blue and gold Macaw yelled his biggest "HELLO!!!!" when he heard us pull up... even though he never makes a peep when it is dark outside.  At least the birds missed us.