Apartment therapy is running such a TreeHugger type survey that we thought that we would just steal it. They are writing from a "parlor-floor apartment in an old massive-walled brick building stays cool with the use of a ceiling fan"- staying cool in the City has its own issues and solutions. They note: "Lots of people use an air conditioner. Lots of others don't, out of environmental concerns, discomfort, or to keep the power bill down." They also point to a very useful guide from RealSimple: 23 ways to beat the heat.