Over mother's day weekend, our neighborhood hosted a huge garage sale. At the end, while driving home, we found this pretty beat up book shelf for free on the side of the road:
It had a notch cut out of it:
So we took it home, cleaned it up, sanded it, and used a piece of wood from our stash to fill the hole:
The template for the hole:
Using liquid nails, we hammered it in place.
Then we used wood filler and our sander to smooth out the hole for painting. I did one coat of primer before using a basic indoor satin from our house paint collection.