I've had a look at this page. To the other days as well. I think it's really an awesome tutorial!

I would say the only thing that I feel is missing is a day about the shell. Maybe proposing a shell different then the default bash would be a bit too much, but editing it's .bashrc file would be cool. Especially on the topic of aliases for commands. This could be also an introduction to having such files in the home directory, like .vimrc.