The hierarchy of resilience:
It's trivial to censor an (average wealth, average risk tolerance) individual -- just harass and prosecute for unrelated things. Everyone is a criminal, once you have enough laws...
It is fairly easy to censor a commercial organization (just cut off their payments and banking...)
It's harder to censor a free site (it can do what everyone is suggesting here; hosting offshore, non-US domain name, etc.)
It is much harder to censor something which can be readily mirrored by others.
It is very hard to censor distribution of a dataset. Even harder if the dataset is very small (sony keys, dvd-css, etc.)
It's almost impossible to censor an idea.