After successfully installing a LAMP stack and Drupal on my Raspberry Pi, I moved to the next step of installing node.js. Since the Whezzy image for Raspberry Pi is Debian Linux it was straight forward to install node.js. In fact I followed my own tutorial with the exception of installing npm. (Npm is now installed with node.js and does not need to be installed as a separate package.) It took nearly two hours to make everything, so be patient. I copied the node.js program from my arduino and node.js tutorial and ran it on the Raspberry Pi without any issue.
The next step is to point the arduino to the Raspberry Pi and then setup Drupal to display the logged data. After that I would like to pull out my old OpenOPC python scripts and start using the Raspberry Pi to communicate with industrial PLCs. Eventually I'd like to setup the Raspberry Pi to replace an industrial PLC. The one spec I need to define is how to handle the IO. The on board GPIO will not be enough to run a machine. Do I use a USB IO adapter, GPIO for communication to the IO, or more arduinos over Ethernet?