TestDrive is a project that makes it very easy to download and run the latest daily Ubuntu development snapshot in a virtual machine. Actually, it can be configured to download and run any URL-access ISO in a virtual machine. But the primary goal is to provide a very simple method for allowing non-technical Ubuntu users to test and provide feedback on the current Ubuntu release under development.
Now you can test Ubuntu 10.10 Maverick Meerkat the easy way and without installing it to your hard drive, TestDrive runs the daily Ubuntu .ISO in KVM by default but can use also VirtualBox if it is installed (See the screensots bellow).
Installation for Karmic and Lucid
sudo add-apt-repository ppa:testdrive/ppa
sudo apt-get update
sudo apt-get install testdrive