Love Cement Tiles! You'll see them used in bathrooms, kitchens, fireplace surrounds, and in/outdoor flooring. There are plenty of beautiful examples on Pinterest. I've used cement tiles in bathrooms, mudrooms, kitchens, and laundry rooms. When you're looking around you may hear the words "encaustic" or "cement" tiles, two terms for two different products.
Encaustic tiles (or inlaid tiles) are clay based, using different colors of clay that are inlaid into a mold, fired and glazed. The term "encaustic" is loosely borrowed from enamel painting process which includes adding pigments to heated beeswax, making an "encaustic" waxy paste that is applied to a surface using different tools before it cools.
Cement tiles are made with "concrete" a mixture of Portland cement, sand, and water. Pigmented minerals are mixed into the concrete to make colors and then poured into a mold. Instead of being fired, the tile is hydraulically pressed and left to cure for several weeks and no glaze is added. However for "slip-resistance" in bathroom applications, after installation, a penetrating sealer is applied.
Here are my favorite sources for Cement Tiles: