1961 penny error

I was digging through some old coins in my house, when I came across this piece of work! From the looks of this coin it literally looks like a deformed coin. Now I want to know if it was done by the mint or by some deranged citizen. Also, if indeed it was mutilated by the mint, how much money...

Dug up this 61' Lincoln cent with no mint mark, which I believe defaults to the Philadelphia mint. The error I'm referring to is on the Lincoln Memorial side which Lincoln is missing from the memorial. Any info or comments from you coin buffs and collectors is appreciated!