My father was doing this with Hydroponics 15 years ago, but it never really took off, and the equipment was expensive. Hopefully it will catch on again.

this is cool, but i have an aerogarden.
it works great and its cheap at Sam's Club right
now. it doesnt spray, it puts the nutrients into
the bottom where the water is contained.
so i think it would work better going directly
into the roots.
IMO

Know what would cost you a lot less and actually grow a significant quantity of food? A five gallon bucket with a 10 gallon tank bubbler in it. Even when you add in a couple of 50 or 100 watt cfls to grow that bucket (go for a couple of hundreds if you want some fat juicy tomatoes) and get some standard liquid nutrients. It's not hard to maintain and can really be done just by looking at the plant's condition. The great thing is that if you watch what you put into the bucket you won't have problems in the first place, and if you do all you have to do is empty the water and put in a new mixture :D You don't need sophisticated measuring equipment to do hydroponics; if anything you can manage the water professionally with relatively cheap ph and ppm pens or strips (if you're too lazy to just measure your nutrients right and start w/ a base of distilled or bottled). The whole setup is still going to be cheaper than one of those countertop models, and you're actually capable of producing a significant amt of sustenance (most ppl could probably provide for all of their fruits and veggies in their spare bedroom if they really got down to it, and still way cheaper than buying the stuff - though you might have DEA agents swooping in on quick lines thinking you've got a hidden pot farm :D)

Anyway, little things like this that bastardize hydroponics make me mad. Sorry if I rant :D This is great if you wanna grow a couple of dandelions in your bathroom.