Wow, this generated alot of interesting responses!
Ryland, once I though of the water idea, I also remembered many Window units use this to increase efficiency of their small condenser coils.
To everyone who talked about humidity, I agree in full with everything said, its amazing how much of a difference there is between 40-50% and 70%+ even at the same temp! We run our portable dehumidifier in the basement and when if it gets turned off for a while you can definitely feel the difference. We often open windows at night to take advantage of the free cool air which most days allows us to coast to a late enough point in the day when its not so hot out again before the house gets to warm. Unfortunately some nights, like tonight, the air is damp, its over 70% RH inside now, so I'll put the output of the dehu blowing into the furnace return vent in the basement with the furnace fan on to circulate cool dry air through the house once its the same temp as outdoors and close the windows, it works very well and the dehu uses around 300w i believe.
On another note, has anyone here heard of the Hallowell Acadia? It's a ASHP that still produces usable heat down to -30*F before finally switching to backup. It uses a booster compressor system to do it. Very ingenious design I think. Unfortunately the company (smal company based out of Maine, went bankrupt due to a high failure rate. From what I gather, Bristol (compressor manuf.) told them to use a certain start relay design that caused major problems and most times ended in compressor death. Hallowell resisted but they gave no other choice so they used it anyway. Sad to see another larger company like trane or carrier didn't buy the technology and fix the flaws. I was sad to see such a great technology die out because of such a simple problem.
Lastly, I started on my water cooling project today. Took a 3ft piece of 3/8"(I believe) clear tubing and drilled 1/16" holes every inch in it. Taped one end shut, and hooked a tiny fountain pump to the other. Depending on pressure I can get anywear from a steady drip to a 3ft spray from this setup. I'm going to test it small scale to see how much of a difference it makes on an old minifridge with coils embedded in one side that get pretty warm. I'm going to do one test with a small fan blowing up the side and see how long it takes to pull down from room 70* to 30* then another test with water running down the side and time the difference. If I had a Kill-O-Watt I could get more useful info but unfortunately I don't and for my boredom inspired curiosity this will do.
I'll post some pics tomorrow.
Adam