If you are reading this, then you must enjoy feeding squirrels like I do. I enjoy all their crazy antics and occasionally training them to eat out of my hand. What I don't like is when they think the bird seed should be for them! They are awfully greedy when it comes to food. I often see them chasing each other away when there is more than enough for them to share.
One thing I did was buy a bird feeder that has a gadget on it that when the squirrel hops on it swings down and closes on the seed and if the squirrel isn't hanging on he has a short drop to the ground. After once or twice of that, they have stayed away from it and are happy to eat any seed that falls to the ground from the birds.
I have put out cobs of corn for them and at first they were picky about eating it, but, when winter came, they were eating like there's no tomorrow. I have seen some squirrel feeders for corn that gives them a little challenge and excercise at the same time. Here is one that I'm tempted to try:

It's a carousel squirrel feeder and it looks like it would give me lots of entertainment as well as give them some exercise as they work on obtaining their much wanted corn. At least the work would be productive instead of trying to get to the bird feeder that never opens for them.

Here is another squirrel feeder that appears to be a little easier for them to handle. You can put peanuts, corn and other large seeds in it. If you use nuts, make sure that they are not salted.
Since I've been feeding my squirrels, they have been much more well behaved than before. I enjoy watching them and they are more willing to let me do that since they have figured out where the food is coming from.