As Play! Framework 2 is meant to be "full stack" and completely integrated, the good news is that there are no specific requirements for you or your environment to start creating new web applications.

However, I could give you some common advice, for example, having random hardware is good enough, but having an SSD can be really helpful. This is because we'll be in the JVM world, where compilations will be needed and thus filesystem access can be intense. So just bring your machine and your preferred text editor (or IDE) and go ahead.