I built a bookcase to cover up this dumb ugly wall leftover from our renovation last year. The wall is double wall thickness on the bottom half, and it has a stupid pipe sticking out of it, and it's generally terrible, but I didn't want to knock it down because the water lines for the laundry room are in the wall.
I didn't take a ton of pictures along the way, because it was a fairly boring project. After getting the cases built and assembled, I did a test fit, which you can see here. I'm going to put a shelf right on top of the pipe so it won't be visible (unless you're toddler height, I guess).
Next I hauled it back out to the garage, built the shelves, then covered up all the plywood edges with solid wood strips.
After sanding and finishing with teak oil, I mounted it in place, attaching it to studs in a few spots.
Lastly, I installed trim around the edges to cover up the gaps, and Carrie loaded it up with books. It turned out really well!