So I converted my friend to Mac OS X and he asked me to come and teach him the basics. I was going to show him how the basics like closing all the windows doesn't quit the program, you don't need virus protection, how to use grapher (he's going to major in math) and some very basic Terminal commands. Any ideas on what else I should show him? I have two hours to teach him before I have to go to my house and get ready for work.