Alright, it's already 12:41 am and I'm still awake because I'm trying out a Java application, which illustrates the use of java.util.concurrent package. The application was called Java Concurrent Animated for fun and practical technical presentation. It is an executable JAR file which is available for download at sf.net/projects/javaconcurrenta (the source code can be downloaded too).
Visualizing the Java Concurrent API Animated
I don't know if the online Java tutorial already have a link to this project (I'm too lazy to check it).