I generally believe that the way to deal with speech you don't like is to counter it with more speech you do like. Limits on speech almost always cause more harm than good, but I sympathize with Hungarians and Austrians who believe that Communist symbols and holocaust denial (respectively) are beyond the pale of public discussion. Considering the millions of deaths attributable to Communists and Nazis I can understand why the people most damaged by those ideologies would want to suppress their resurgence. Still, I tend to think that it would be better to fight bad speech with good speech rather than coercive government force.
Eugene Volokh agrees, as I figured he would.