There is a lot of good information here for me too since I live in Queensland, Australia and have no AC. During summer my boys get some extra fruity treats - watermelon and Monty loves my pineapple ice blocks/ice lollies (made from 100% fresh pineapple and juiced and frozen by me).
When I am at home, my boys spend part of the day out on the balcony, because it's much cooler there than in the rest of my apartment, otherwise I find that the bathroom being mostly tiled is a cool room.