x86 emulator in Java!

At this moment I couldn't imagine any real application for it, but it doesn't matter: it is fun!
The JPC is a x86 emulator and the team was able to run DOS and Linux in a applet, completly open source it is a great knowledge source.
Take a look on their page, try it playing Lemings or other nice game: The JPC Project: Computer virtualization in Java.