how can i remotely access other PC's with it? can i use Terminal for that?
You can access other machines with POSIX-based OSes with the ssh command. Syntax would look like this:
There is virtually no limit to what you can do from the command line. Add a package manager like MacPorts or Homebrew and you can add fun stuff like
cmus,
tmux,
byobu, or
htop.
There's also things that require fewer software prereqs like
ttytter, a CLI Twitter client and
ToDo.txt, a script that lets you keep a simple to-do list.
If you're serious about using the terminal, start by reading The Linux Documentation Project's
Bash Guide for Beginners. That's an excellent place to start since it will give you a more cross-platform view of how the CLI works. Additionally, if you want a book, I heartily recommend
The Mac OS X Unix Toolbox. I'm guessing that it might be a little out of date at this point, but the core CLI functionality hasn't changed appreciably since Leopard.
You'll probably also want to try out using either
TotalTerminal or
iTerm2 to keep a command line close at hand with a pop-down Quake-style command visor
But basically, there's not much that you can do from the GUI that you can't do, and probably do better, from the CLI.
