Selenium Node configured to run PhantomJS.
Images have been created based on Selenium images: https://github.com/SeleniumHQ/docker-selenium
First, you will need a Selenium Grid Hub that the Node will connect to.
$ docker run -d -P --name selenium-hub selenium/hub
Once the hub is up and running will want to launch nodes that can run tests. You can run as many nodes as you wish.
$ docker run -d --name selenium-node-phantomjs --link selenium-hub:hub totaldesigner/selenium-node-phantomjs