You mean a CD/DVD, USB device that you can boot from, and run the same install as the one you have on your hdd now?
Depends:
not without a lot of trouble concerning CD/DVD
yes, you could ‘dd’ the entire install, incl. homedirs etcetera, to a USB disk, change some config files, boot from it and run it. I used to have such an install before LiveCD’s were common.
you could also simply perform an equal install on a USB disk, and create and use partitions on that disk.