While we've all focused on the dangers of radical Islam and of Islamist terror, the attack in Norway should remind us that there is actually a pretty large problem with other sources of terrorism in the west. The European Union's 2010 Terrorism Situation and Trend Report had some fascinating findings. It showed that of the 294 terror attacks committed in Europe in 2009, only one was conducted by Islamists. That's a third of one percent.
The most recent statistics show that there were 249 terror attacks in Europe in 2010. Only three of those attacks were carried out by Islamist terrors. (Source)