Under Stairs Storage
Wasted Spaces. Almost every home has them—but cookie cutter homes are notorious for wasting space. In fact wasted spaces are so pervasive that there is even a home improvement show called "Wasted Spaces".

It is hard to blame developers. They need to make a profit, and I doubt that most people are willing to pay extra to utilize every inch of space. Notwithstanding, here in California where space is at a premium, it is convenient to utilize every bit of available space.
Long ago, I discover that my starcase was almost completely empty inside. This was a huge wast of space. I pondered for several years on how to use this space. I was ultimately able to reclaim forty-four cubic feet of space for storage.
The main difficultly in the project was working around the heater return. There was nowhere to re-route it to, so I had to build a 2×2 frame around it to support the main cabinet. Behind the shallow cabinet is another deep storage compartment.