As you probably already know, Akka can make your life a lot easier when it comes to things like concurrency and scalability. A very typical use case for starting to use Akka is when you have a computation or algorithm of some sort that lends itself to parallelizing. Implementing that with just core Java is cumbersome, error prone and it will feel like you are reinventing the wheel every time you do it. Akka will, for example, enable you to take advantage of all the cores in your CPU, or maybe even the CPUs of several machines, without having to worry about the evils of things like threads, lock, semaphores etc., and not to mention the hassle of trying to distribute the computations.
