Sm2ke420, I had this saved in my favs, I'll share it here with you, its cheap and easy.
You will need:
1. A five gallon bucket
2. A "muffin" fan, or a round fan of some sort that has the motor built into the compact frame of the fan.
3. A drill
4. A one pound container of Soil Moist, which is a water absorbing crystal. You can find it at almost all nurseries and grow shops.
5. ONA, or Odor Neutralizing Agent. YOu can get it at most grow shops or "baby" shops for new mommies.
6. A 5 gallong bucket lid, which may be optional.
Step 1
Get yourself a muffin fan, or a Durex brand or Holmes brand circular fan with base. They are very common at Wal-Mart and can usually be bought for less than $8 US. The reason you should get this brand of fan is because after you have removed the base, it fits perfectly into a five gallon bucket.
Step 2.
Using a flat screwdrive, pry of the nubs on the base and remove the screws.
Step 3.
Remove the fan from the base. Keep all the parts in case you might want the fan again someday.
Step 4.
Place the fan into the five gallon bucket, frontside up. If you bought the holmes brand fan it will fit VERY snugly. You don't even have to secure it in place.
(If it is smaller than the opening, then cut a hole, smaller than the diameter of the fan, into the bucket lid. Use some floral wire and secure the fan to the lid so that you can place the lid onto the bucket.)
Step 5.
Drill about 8 or 10 holes around the bucket.
Step 6.
Remove the fan/lid and put about 9 cups of water into the bucket. Then put about 1 cup of the ONA into the bucket and mix it up. Be careful, it can smell pretty strong at first.
Step 7.
Put about a cup or two of the soil moist into the bucket. Make sure that all of the liqued is absorbed. You don't have to use alot! The crystals expand to about 50 times their size.
Step 8.
Set the fan on the lowest setting and put it back on the bucket. Plug it in and put it somewhere in the corner of your grow room. I don't actually have mine in the closet itself...
You will notice a difference in about 5 minutes!
The great thing is that the Soil Moist is re-useable. Once it dries out, mix up some more water/ona and pour it right in.
You may need to tweak it for your own grow room, but that's the basic design. Thanks!