A fan asked if I would buy and try Qiqo Handy Cooler.

The Handy Cooler uses 'evaporative cooling'. (This principle has been around for years, and even this device I see, has been around for more than ten years.) You wet the included cellulose-cooling filter (i.e. sponge) and place it inside the Handy Cooler. The turbine (i.e. plastic fan) draws air through the moistened sponge and directs the cool air to you. The company says The Handy Cooler can make air up to 30°F cooler, but that optimum-cooling performance is achieved under hot and dry environments. The fan speed is variable up to a “15 knot breeze”. (I have no way to check that out here at Gizneyland.) The Handy Cooler is all plastic, but seems well made. The “30dB whisper-soft turbine” is pretty quiet, especially at the slow speed. To operate the device, first add water to the sponge via a small water bottle that’s in the kit. They caution not wetting it under a faucet as you might over-wet it, and end up with water dripping from, or into the motor of the machine. A nice feature is the airflow vent, which is adjustable through 90 degrees. It runs on 4 AA batteries or a USB connection. I used an infrared thermometer to check the air coming from the machine and found indoors it dropped the temperature by about 10 degrees. But it was a very hot day when I did it. $40 bucks seems a bit expensive to me, but operating it on battery is really expensive. The company says it will run for four hours on a set of 4 AA’s. You can't recharge batteries in the device, so rechargeable batteries and external charger might be in order if you use this a lot. You can use the included USB cable and run it from your computer. I also found you can run it via a stand-alone back-up battery USB charger. Available in black, blue, or pink. 

http://amazon.com/dp/B002F8IFV6/?tag=twnene-20

If you don't mind waiting two weeks or more you can buy it from overseas on eBay for under $15. This link was still working on 5/25/13. UPDATE -- THE COOLER IS STILL THERE, BUT SOLD OUT. YOU CAN CHECK BACK TO SEE IF THEY RE-STOCKED IT.
 http://www.ebay.com/itm/USB-Mini-Portable-Handheld-Air-Conditioner-Cooler-Fan-/130576483446