[lihaoyi]

If you're interested in Actors, the book has a chapter `Chapter 16: Message-based Parallelism with Actors` that does an introduction to them, and they are used "in anger" in `Chapter 18: Building a Real-time File Synchronizer`. I've worked hard to make this the best introduction to real-world use cases of Actors I've seen anywhere on the internet.

For simplicity, it uses a tiny Actor library instead of a big framework like Akka, but all the concepts and techniques should be transferrable to any Actor-based application