Not shy or retiring, the owners of these areas went that extra step to elevate the look with the use of glass tile, a wine cooler, and glassing in the wine cellar.
They could have just stuck a bar cart in the space under the stairs, and the wine cellar could have just been some wine racks hung on the wall, but the extra investment and time give both spaces a punch and drama that are enjoyed by all!
The area on the left has shelving that is installed away from the back wall and the lighting is put on the back edge of the shelf so that the wall is washed in light.
Take note also that each area is clutter free, and has good looking accessories that finish the look.
It doesn't have to be a bar or wine cellar under your stairway, but whatever you decide to put there, consider going a step further than you would at first think of, use great lighting and consider your accessories carefully.
You don't have to just pass by that under the stairway space - you can add drama and usefulness to the area, and your life.