A shortest complete list of packages that should be installed on a Debian system to repeat current configuration can be obtained by the following command:

aptitude search '?installed?not(?automatic)?not(?reverse-depends(?installed))'

To use output in scripting add a key: -F %p

This package list can be passed as an argument list an apt-get install program on your new system.

How to register your private key on the remote SSH server running on Linux

I've forgot which program from SSH toolchain does this (ssh-copy-id), and replaced it with my own method.

ssh-keygen -y -f ~/.ssh/id_dsa | ssh remote.org tee -a ~/.ssh/authorized_keys

~/.ssh/id_dsa should be replaced with your private key file.
remote.org - SSH sever address