I get mail from LJ users all the time (because I have "hacker" by my name on the staff page?). This one is pretty good: this user is concerned about someone who claims to be able to hack them. They quoted a comment from the "hacker":
"It would take me 1 min to find your ip address and i would be on your comp doing crap that would piss u off i could over clock your pc making it fry up.... i could put anything i wanted on your pc all at a key stroke u have no idea what a hacker can do and u have no idea how to stop it. so dont think u can do crap when u have no idea how i can do it becuse i have learned how through c++ and many more books.