Two cool and important things I learned the other day:
First, I learned how to use byobu/screen, most importantly to let a process such as irssi run on a tty and in a GUIterm.
Second, I learned that GUI programs WILL FAIL if you don't own some X for them to run on. Thus, it is impossible to start a GUI program, log out of your GUI session, log back in to your GUI session, and have your program still running -- even if you use something like screen.
Also, you can
alias aptget="sudo apt-get". On Ubuntu-likes at least, this saves you about six keystrokes every time you want to install/remove something. You could
alias aptget="sudo apt-get install", of course, but then you can't use it to remove stuff.