Re: HOWTO Reinstall all of your current packages if you do a fresh Ubuntu install
Another tip is that if you have a download cap/slow connection, and are duplicating a system, you can move all the .deb packages that you want from /var/cache/apt/archives on the source system to the same place on the target system. Apt (or synaptic) will automatically detect that it has them and not bother downloading them all over again.
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