Make A Shutdown Timer !

METHOD # 1

Right click on your desktop and choose "New=>shortcuts".
In the box that says "Type the location of the shortcut",
type in "shutdown -s -t 3600" without the quotation marks and click next. Note: 3600 are the amount of seconds before your computer shuts down. So , 60secs*60mins=3600secs.

Another addition u can do is displaying a message with it then add a bit more...
shutdown -s -t 3600 -c"This is the message" (use " " with c)

Make up a name for the shortcut and you're done.
You can change the icon by right clicking=>properities=>change icon=>browse

TO ABORT:
To make an abort key to stop the shutdown timer just create another shortcut and make
the "location of the shortcut" to " shutdown -a" without the quotes.

METHOD # 2

{EASIER THAN THE PREVIOUS ONE}
Here is another trick to shutdown at a specific time, for example you wish to shutdown at 11:35am. Type this in
start=>Run
Type Code: at 11:35 shutdown -s
TO ABORT:
Code: shutdown -a

Try this and think of what pranks you can play with your friends with this,like change its icon to internet Explorer and rename it and whenever one will open IE the windows will be shut down.