I've always wanted to build a little aeroponics setup ever since I read some articles about NASA developing aeroponic grow chambers to use on really long space missions. Since we've moved from the gulf coast up to the mid-west, it would be especially nice to have some healthy growing things to brighten up the house during the winter.
There are little kitchen appliances you can buy that grow tomatoes and herbs using an aeroponic method, but where's the fun in just buying one? Much better to build it.
First we need a utility tub as the root chamber where the nutrient ladden fog will be applied.
Now that blue or red LED Christmas lights are common and inexpensive, they make a good light source. They have really low power consumption compared to other types of lights. Why not a white light source? Plants don't use the green part of the spectrum (that's why they look green), so it's a waste of energy to generate white light when we could just generate the red and blue that they do use. To turn a string of ordinary Christmas lights into a plant light we can mount the lights on a sheet of white foam board.
Next we need an ultrasonic humidifier to generate the fog to apply to the roots. Rather than just water in our humidifier though, we need to add some water soluble fertilizer.
We also need to modify some plastic pots so that they become "net pots", basically just slice lots of holes in the sides so the roots can grow out into the fog chamber.
That's it. All told it looks like a home-made aeroponics setup would run about $100, the largest chunk of that being the ultrasonic humidifier ($30).