The Norfolk and Western, having access to virtually free coal, developed some steam turbine locomotives in the '50's. Many were still running into the '60's, long after every other mainline railroad in the U.S. had abandoned steam. These ran just like a diesel electric, with the turbine powering a generator which supplied power to electric traction motors on each axle.
If there is any future in steam locomotives, it would look more like this than the old, traditional reciprocating steam engines. Not nearly as romantic, but far more efficient.