We have laws against incitement to racial hatred (while I appreciate their effect, they definitely wouldn't pass the US constitutional test; the equivalent for Europe, which is much more ambiguous, is the European Convention on Human Rights:
ARTICLE 10
1.Everyone has the right to freedom of expression. this right shall include freedom to hold opinions and to receive and impart information an ideas without interference by public authority and regardless of frontiers. This article shall not prevent States from requiring the licensing of broadcasting, television or cinema enterprises.
2.The exercise of these freedoms, since it carries with it duties and responsibilities, may be subject to such formalities, conditions, restrictions or penalties as are prescribed by law and are necessary in a democratic society, in the interests of national security, territorial integrity or public safety, for the prevention of disorder or crime, for the protection of health or morals, for the protection of the reputation or the rights of others, for preventing the disclosure of information received in confidence, or for maintaining the authority and impartiality of the judiciary.
http://www.hrcr.org/docs/Eur_Convention/euroconv3.htmlIn addition, the Labour government is trying to get a bill
criminalising incitement to religious hatred through Parliament (currently blocked in the House of Lords). That I'm definitely unhappy about - religion is a matter of choice, and some religions can be appalling, so hating them is perfectly justified.
The particular act (about 'serious crime') had the ban on demonstrations in central London that hadn't been arranged with the police beforehand inserted, MPs were told, to get rid of one man who has been camping on the green outside the Houses of Parliament for about 4 years (I'm not sure what his original protest was; recently it's been anti-war). In either an amzing bit of incompetence, or a cunning sleight of hand (if that was never really their intention), the bill has turned out not to apply to the man, since his protest had already started; it's only new protests, such as this one at the Cenotaph (up the street from Parliament) that are now banned. If the section of teh act had been presented to MPs as "ban demonstrations outside all the government offices", I wonder if they would have accepted it; but that is the effect it has had.