Screenshot of website using php on linux using PhantomJS WebKit
Main project page
http://phantomjs.org/download.html
Setup your environment
http://devlup.com/javascript/setup-phantomjs-on-amazon-ec2-instance/4468/
Setup your script
http://devlup.com/programming/php/capture-webpage-screenshot-using-php-and-phantomjs/4484/
Additional reading on the PhantomJS
http://pielmeier.blogspot.ca/2011/02/headless-html-page-rendering-with.html
http://stackoverflow.com/questions/3342966/taking-website-screenshot-server-side-on-a-linux-rented-server-free