What's next?

I stopped with Scala. It is really powerful, amazing and flexible language but now I can not find its use in everyday work. It doesn't mean that it was wasted time. I think this lecture broadened my horizons significantly. What's next? For some time I'm interested in performance tuning in Java. It just so happens that it was talk about this on Warszawa JUG meeting recently. The Speaker had prepared program that simulates load encountered in High Frequency Trading applications. He showed how can be the performance affected by setting various JVM parameters. Application code is available on GitHub. In the near future I'm going to try this.
In addition next week I'm going to Krakow for the GeeCON conference and after that I'm going to describe my impressions there...