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.
Install testdrive and gtk frontend using the following commands
Open the terminal and run these commands
sudo add-apt-repository ppa:testdrive/ppa
sudo add-apt-repository ppa:testdrive-gtk/ppa
sudo apt-get update
sudo apt-get install testdrive testdrive-gtk
Now you can Launchd TestDrive via Applications > System Tools > TestDrive GTK Front-end
With Ubuntu TestDrive, you can try beta release of Ubuntu 10.10 without affecting your current installation. Ubuntu TestDrive is a set of ISOs that can be run in a VirtualBox or KVM virtual machine.Currently, TestDrive doesn’t work with VMWare.