Node.js vs. Fat-Free vs. Play

Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.

Fat-Free Framework makes it easy to build entire Web sites in a jiffy. With the same power and brevity as modern Javascript toolkits and libraries, F3 helps you write better-looking and more reliable PHP programs.

Play Framework makes it easy to build web applications with Java & Scala. Play is based on a lightweight, stateless, web-friendly architecture. Built on Akka, Play provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications.