A modern - and easy to install - shower wall panel are these high gloss wall panels. They look like back painted glass but are lighter and cost less. Learn more here - http://innovatebuildingsolutions.com/products/bathrooms/high-gloss-acrylic-wall-panels
Prefab shower niche $67. "sized to fit between studs and are the perfect depth to slide into a 2x4 wall cavity. They are adhered between the studs with an acrylic sealant, and mesh seam tape then is applied over the joint between the niche and the wallboard. Once the unit is in place, you can tile over it using latex-modified thinset... always start to tile before cutting out the niche (to ensure tilework lines up)."