There's only a few weeks left until KDE 4.4 will be released, but being released this morning is the first release candidate of the KDE 4.4 Software Compilation. 
Picture a "test pilot" and you'll probably imagine a dashing personality ready to risk life and limb in order to test the latest technology. The Mozilla Test Pilot program is a lot like that, except you don't have to risk life or limb, and it might not give any great stories to tell at the bar. 
If you've ever used or witnessed a virtual machine in action then you know how much versatility they offer. If you've never experienced a VM, then you are in for a serious treat. A virtual machine allows you to run one operating system on top of another, without effecting your main (host) machine.