This is a small test of whether or not you are vulnerable to the Java7 zero day exploit. The applet on this page does nothing more then start up a (harmless) program depending on your platform. If you see a program staring as you visit this page, then disable Java in your browser immediately.
The code is the cleaned up version posted by beltorak, after an initial walk-through with explanations was provided by argusdusty, on reddit. It was decompiled by benmmurphy, and was originally posted on damagelab.