Do you have a LAN (Local Area Network) ? Now you can shut down your PC from your friends PC who is in the same LAN....pretty useful if u wanna stay over for a longer time...Here is the way to go about doing it.
1. Right click on desktop, create new short-cut.
2. Type shutdown.exe -i
3. Click next, type in name for your short-cut e.g. shutdown computers
4. Click finish.
5. Run the short-cut you just created. Now you can browse the network for computers to shutdown/reboot etc. or just type in the IP/Name of the computer.
You can even broadcast a message, and schedule the shutdown.
Cool for sysadmins.
NOTE: You will only be able to shut down computers that you have admin access on!