Launch app with Java Web Start:
Shutup is a lightning talk timer application written in JavaFX. When time runs out, a several sounds play, including the authors of the application yelling "Shut up!" as a group.
At the Java Posse Roundup 2009 a bunch of us iteratively designed and coded the application as a JavaFX exercise. It proved so useful during our lightning talks that we continued to enhance it for the Java Posse Roundup 2010.
Browse the source code.