Howdy,
Another Do-It-Yourself mist system si:
http://www.trix.com/binx/mister/
Ignore the software code and just use a sprinkler timer like the other posting shows. I built my first misting system using the pump-up bug sprayer and sprinkler timer. Where things didn't work out so well was that I like to run twice a day for 20 minutes. Even though it only used about 2 quarts of water, it used up most of the pressure in one day, as I recall. I wasted a lot of time and money experimenting - it's in my nature
Of course, I'm still tinkering with my final (?) solution. It uses a 300W Hydor in-line pre-heater to warm up the water to about 90F just before and during the misting. I still use the sprinkler timer and valve, but as a bypass to help flush out the cold water still in the lines from the last misting. And I now mist three enclosures instead of one. So that is 6 quarts a day total. The PM-60 pump works fine whether is is one nozzle or a bunch.