Here is a really fun project.
The idea is to place an ear of feed corn on the nail (sticking up through the table top).
Be sure to slightly dull the point of the nail for safety reasons.
The squirrel will actually sit in the chair, at the table, and eat away.
I noticed they like to eat the 'hearts' of the corn kernels first so I do not put another ear of corn out untill they clean up the remnants below the feeder - which they will do if you wait.
The backboard is optional but helps to stabilize the chair when attached to round objects such as trees.
Click here to download the plans in Adobe Acrobat (pdf) format.