If you're running Ubuntu 9.04, 9.10, or 10.04, it's trivial to testdrive Lucid in a virtual machine, without modifying your current installation!
If you're already running Lucid, congrads! All you need to do is add the testdrive ppa, and install testdrive, and either kvm or virtualbox-ose.
Just pop open a terminal and run:
sudo add-apt-repository ppa:testdrive/ppa && \Then you can either run testdrive from the command line, or use the menu, Applications -> System Tools -> Testdrive.
sudo apt-get update && \
sudo apt-get install testdrive
Then, a menu will pop up, with a menu of Lucid daily images. If you have previously downloaded any of these, you should see a timestamp of the cached file. If you run testdrive everyday, your cache will stay up-to-date, and the incremental download will be much faster!
Select one of the offered ISOs, or enter a URL to another one of your choosing, and you should be off and running. Help us make Lucid Lynx the best Ubuntu to date!