Yup...I've solved it..well, 98.3521%...

I have a couple of those simple vertical bird feeders with openings in the side...they have a wire loop at the top. When I first got them, the squirrels would shinny down the chain and chew up the feeders...I took a piece of aluminum siding and poked two holes in it to match the wire on the feeder, then popped the wire out of the feeder, threaded it thru the aluminum..(about a 1 foot square)...and put it back on the feeder (which has a pointy cover).

Now I have a feeder with a roof...a wobbly, wide roof! It hangs from the gutter in front of my picture window by a small chain. The silly squirrels climb down the chain and try everything to figger out how to get around that unstable barrier. I saw ONE actually hang by his back toes, reach WAY down, hook one from paw in the window of the feeder and do a wild swing around so he could catch a hold and hang there awkwardly and steal a few nuts, but usually he just missed and fell to the ground.
   A few times, a more athletic one has made a wild leap from a tree limb or the window to grasp the feeder, but this only works maybe 1 out of 20 times, so they usually just give up.

   I suppose if I made the 'roof' a couple inches wider and hung it all further away from the house, (like on a special pole), I could reduce successful attempts to about zero, but the entertainment value of making it 'almost' possible is worth it!