Having lived in NYC for 20 years, you often forget that the rest of the world has all these little perks around their home because they're not super old. Case in point: a shower niche for shampoo, soaps, sponges, etc. When you are living primarily in small prewar buildings, you're lucky if your door doesn't hit the toilet.
In renovating this 1945 row house, I was asked by the contractor, "Would you like a shower insert?" Um, yes. Most of us without this feature use those over-the-showerhead organizers and it can be a nuisance during a shower to reach up there and grab what you need. In this situation, I still had to place it on the same shower wall due to space constraints, but it's below the showerhead. The other nice thing about having it away from the stream of water is that moisture won't settle in the nook as much as other areas, keeping mold and mildew at bay.
I struggled with whether to leave the niche finished with the same subway tile on the rest of the walls in the bathroom, or do something a little different. I went with a pop of mosaic and some white quartz to frame the transition from the subway tiles to the special, little niche. I got inspiration from a Pinterest post of course (right image below). When complete, I'll post the end result for all to envy (me included, I still have the metal thing hanging off my showerhead).