I really like shower curtains in a standard bathroom, shower/tub combo. The reason being is I think they look cleaner, more modern and more relaxed than glass sliding doors. This is one of the easiest weekend projects you can tackle yourself in a few hours and add instant update to your bathroom style.
I am torn. I either really like layered, linen/cottage/country looking shower curtains or really bold modern prints. Whatever your taste, this project is a great one because it frees up interstitial space and breaks down the boundary imposed by a shower door making your bathroom seem and feel much larger. A bonus is many showers contain an overhead window or skylight so pulling back the curtain when not in use can really add some gorgeous glow into your space.