I'm curious to see what people have used genetic algorithms for in practice. Personally I've used them for feature selection when I was trying to reduce a high amount of features to smaller amount for a classification problem.
Google "applications of" genetic algoritms. I got results that way years ago. The abstracts of conference papers are also informative. I remember them used for scheduling/planning and optimization problems. One person even made one to find the optimal set of compiler arguments to get best performance for Haskell programs. Look up Humie Awards for Genetic Programming for a long list of human-equivalent achievements too.
A grad-student-colleague of mine developped a control system for a robot using hyper-redundant binary-state actuators using GA's to search the solution space.
Of course they're definitely great for evolving little cars, like this other example shows: http://rednuht.org/genetic_cars_2/