We have a room downstairs that has served as a guest bedroom/computer room. The room is larger than our guest bedroom, so it really needed a purpose/something to fill it. Enter the library idea, inspired by Christy's friend Beverly's recent addition. We didn't want anything too elaborate (codeword for expensive!), so I drew up some simple plans with the idea of using cheap pre-primed wood. The room has a large window but remains rather dark during the day, so extra money spent on hardwood would probably go unnoticed anyway. We had to wait several months, but we finally found someone to build it.
The left side needed a shorter depth due to a closet door, so I decided that the first column of shelves could accommodate media, while the rest of the shelving would be traditional book shelves. On the right side you will notice cabinet doors. That cabinet is hiding the two breaker boxes. The cabinet will also serve as a hiding place for the cabling/wiring connected to my computer, which is actually housed in another room. The corner computer desk is nothing fancy, but it is just about perfect from a size standpoint.
So maybe it isn't grand enough to call the room a library, but it will hold a lot of books. I still need to do touch-ups/paint, which is why the shelves are ignominiously bare.