Hudson CI - since I am increasingly dealing with JVM languages, something like this would be quite interesting. A Continuous Integration platform in and for Java (and also usable for other purposes). Interesting, especially the easy installation - just a .war file that you start or throw into a container and then configure via the web interface. Continuous Integration greatly helps with deployment, especially when you build your projects cleanly with unit tests. Manual execution of the test suite is then largely eliminated, as the CI server takes over and can, for example, automatically deploy cleanly running builds as beta or provide working snapshots (in the sense of the test cases working) as downloads.