CQRS is of great use for building things other than server side systems as most people tend to use it for.
Watch this SkillsCast recording of this talk by Greg Young and learn about the use of CQRS in other kinds of systems and how it can greatly decrease complexity while providing value to users of the system.
If you are interested in CQRS, may like to check out more here:
CQRS, not just for server systems
Greg Young coined the term "CQRS" (Command Query Responsibility Segregation) and it was instantly picked up by the community who have elaborated upon it ever since.