If you're a PHP developer and have ever wanted to branch out into learning another language, Node.js is a popular choice right now. To help you ease into some of the concepts that Node development involves, Francois Zaninotto has come up with his "Node.js for PHP Developers" series of posts (4 of them now, one previously mentioned here):

• Part One - Event Driven Programming
• Part Two - Modules, Packages and the Strawberry House
• Part Three - Exceptions and Errors
• Part Four - Streams

in each article he provides code examples showing "the Node way" versus "the PHP way" to do various things. It's a great little series and can definitely kickstart your Node.js knowledge.