BipNelly

keystoneanglers has the right idea. I made 4 feeders very similar to his. Work very well. I think it cost me around $15 for a pair.

Small differences in mine, I drill a couple holes through it and run small chain through it. I hang mine from trees using one nail. Brother made one with a wooden base as previously described. He wasn't as happy with his because you had to have relatively flat ground, thus limiting it's use. Also, more accessible to ground critters. His cover was ate off in two days.

Hosser's idea looks interesting as well.

Good luck.

Bldhound

In the past I have used a 3 liter coke bottle held upside down by twine that they could bump with their head to get the corn, works good but you have to fill them often.

Snoogsdad

We started out with gravity feeders about 12 years ago. You could go broke real fast keeping them filled with shelled corn. We now use garbage cans with automatic feeders attached to them. They hold about 200 pounds and depending on the timer settings, can last for up to a month. My web site has more information if you're interested.