So here's a bit of necessity inspiring change.

The air conditioning in my apartment has been broken for about a month now.  I live in South Texas, and the daily temperature is already approaching 100 degrees.  Right now, 10 PM, the thermostat in my house reads 93 degrees.  I have the ceiling fan on, and a door open for some heat exchange.  

Short of going out and buying 10 rotary fans, anyone have any suggestions for reducing temperatures, and thereby saving electricity when the A/C does get fixed, that are practical in an apartment?  As it is, I fear I could be putting a drain on water resources just by replenishing the sweat. =D

Foam gaskets behind switches and outlets reduce air leaks significantly for minimal cost.  Weatherstripping any window or door that leaks (easier to check in winter).  But compact fluorescent lamps (less heat to a/c away, less electricity to use.  Insulate water heater (and pipes going into it) especially if inside conditioned space.

Shading for windows if possible.  Ask landlord about reflective film on windows.

Off the top of my head.

My apartment has a huge picture window that faces south, which means my living room gets stifling on summer afternoons.  I bought mylar curtain liners, and they made a huge difference.  About $5, trim to fit.  (You can even use them without curtains, though it looks a bit tacky.)  They make the room a bit dark, but you can open them when you get home if you want more light.  Keeping the sun from shining in all day makes a big difference.  
If the humidity isn't too high, you can tack a loose weave towel or curtain over a doorway, wet it, and then use your fan to blow air through it (improvised swamp cooler).  If you have a bathtub, you can partly fill it with water, wait a couple of hours as the water cools evaporatively (assuming the drain seals well), and then take a cool bath. The idea behind both of these approaches is to augment the natural human cooling system, sweating.
How about a glass of ice water?

The reciprocal for those of us in the colder north: the house is too cold?  Put on a sweater.  Why heat/cool the rest of the space when you can heat/cool the person instead?

I lived in a similar situation. What helped me: take empty 2L milk containers, fill 'em with water, then freeze 'em. When they are solid, you can place them in front of your fan (in a bucket or plant tray). It really helped, but it's a bit of a pain trying to keep large amounts of ice on hand. Still, useful in emergencies (eg. blast furnace with no AC).