Examples from the book Node.js the Right Way: Practical, Server-Side JavaScript That Scales by Jim R. Wilson
The shebang line #!/usr/bin/env node --harmony works on MacOS, but not on Ubuntu. As a workaround, you can use a wrapper script like node-harmony in this repository. Just place it in your path (e.g., /usr/local/bin/) and use the shebang line #!/usr/bin/env node-harmony.
Chapter 6 is using functionality which was introduced in Node.js 0.11, available for Ubuntu as PPA:
sudo add-apt-repository ppa:chris-lea/node.js-devel
sudo apt-get update
sudo apt-get remove nodejs-legacy nodejs # conflicts with chris-lea package
sudo apt-get install nodejs