Apart from the obvious restrictions on holocaust denial and related socially incendiary language, there have been laws passed criminalizing hate speech.

Hate speech is defined pretty broadly so something as harmless as - free translation - "man, what a schlong!" directed against a state-level politician caused a small media storm and included the police raiding the house (well... they didnt' even manage to raid the correct house) of the person who typed out that tweet. (#pimmelgate if you want to look it up)

That's not to say that there aren't more vile comments and death-threats that maybe deserve to be looked at a little closer to protect the victims, that are also the focus of these legal tools. But in general it seems something prone to abuse of power, and hosting providers can, to varying degrees, be coerced into aiding the state agents in enforcing these laws.