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I was thinking that I could make a small 4GB partition on my 320GB hard drive. This small partition could be used as a live install partition. What i would do is I would make the partition, boot from it, then use the boted live isntall to install ubuntu to a different partition. then I would boot from the newly created partition and change the live install to a different live install. then i would boot from the new install and install to another partition. then i would do the same 1 or 2 more times. Dont ask me why I want to install the 3 or 4 different derivatives instead of just installing multiple desktop environments on one install. I just do.