I have uploaded my code here http://viking-helmet.herokuapp.com/projects/files/Galileo_NodeJs_SSD1306.zip
The code contains a port of the Adafruit_GFX Arduino library to Js. Not all functions have been tested, etc.
Extract the zip file on the Galileo and run npm install the directory you extracted the files to.
You need to have a linux image with a full GCC tool-chain in order for npm install to properly compile the i2c and epoll node modules. I know it will work with the Intel IoT-Devkit (https://software.intel.com/en-us/iotdevkit) but it should work with any linux image that has a GCC tool-chain and node-gyp installed!
P.S. I plan to write up a mini tutorial and put it on my site eventually, but in the mean time the code will have to do.