Aliens on Earth
Alien Invasion
Children's Series
Disaster and destruction
Life in the Future
Parallel Universes
Spaceship based
Superhumans
Space station based
Time travel based
Vehicle based
Anthologies
Misc
see also: science fiction television, science fiction sitcom, List of science fiction short stories
... for a clear discussion of two prominent proposals. Examples of existing "digital rights management" and "copy protection" systems: ...