Don't forget the ceiling fans also. We just have a couple window A/C units but after I installed a couple ceiling fans those window AC units can almost keep the whole house cool if I wanted to. Before the fans we would have to keep the doors shut to keep the cold air in those rooms. Also don't forget the window coverings, keeping the curtains closed to keep the bright afternoon sun out so it doesn't heat up everything helps out too, plus you get to run around the house with fewer clothes <img src="/images/graemlins/smile.gif" alt="" />