Cyber Bullying

I have been working in an 8th grade classroom all year, and I have rarely seen any bullying going on right in front of me.  However, I hear a lot about the bullying that goes on outside of school.  I have been thinking a lot about making the classroom a utopia away from the rest of the world they will have to deal with, but what do I do when most of the hate is taking place outside of school?  Obviously the bullying that is taking place outside of the school grounds is affecting the students when they come back to school.  They know which one of their peers is talking about them online, or harassing them on the phone via texts, so when they come to school being around their peers is very uncomfortable. 
Thinking about facebook, and students with cell phones, and all the internet access that students have before they can even drive boggles my brain sometimes.  I feel like I would have been so overloaded as a student.  Dealing with peer pressure at school was bad enough, but adding in all the new extra ways that students can feel excluded and banished would be overwhelming.  It feels like students are able to hide behind the internet and express anything that comes into their head instantly.  They do not have to practice filtering the things they say because they did not have a face, a person, right in front of them showing them the effects of their words.  This generation of students, not having to face the consequences of their actions immediately, is becoming more and more bold with the things they say about each other.  How do we monitor our students on the internet? What can we do if most of the bullying is taking place outside of the utopia we are trying to create?