Rain barrels; 50 gallons for about $100. One time price. That's only enough to do about 100 sq ft at a time, but with one at each corner of the house maybe you can make a difference, depending on the size of your lot. And you win twice, because you are not paying the sewage price on water which doesn't go in - or out. For about $30, you can build your own. In this area, there are several people on craigslist selling pickle barrels and other food grade barrels for $15-$20.http://raleigh.craigslist.org/grd/3264205445.htmlJust add your own spigot and cut hole in top for downspout.Or you can buy a finished one for about $50. Plenty of people are buying the above barrels, adding the hardware and reselling as rainbarrels.The problem with rain barrels is that they're not that good for watering the lawn. After using all the water for the 100 sq ft of lawn, you have an empty barrel. To refill, you need rain. If you need to refill your rain barrel on a frequent basis, you need frequent rain. If you have frequent rain, you don't need to water. If you don't need to water, then you don't need rain barrels.I view rain barrels as a source of water for flower pots and vegetable gardens. They just don't have the capacity to keep your lawn watered.