A computer can be shut down by just pressing the appropriate button on the CPU, but there are many other options available.
You can see them all in PowerOff, a small tool that enables you to automate your computer's poweroff.
In fact, this is quite a poor definition because PowerOff allows you to choose between different actions (shut down, log off, hibernate, restart, lock and more), schedule them or even set the PC to be shut down after a given process is complete.
What's more, you can use it not only on your own PC but also on remote computers. The only feature I missed was the possibility to shut down the PC according to network usage.
The program shows a warning before performing any action, which is good because it acts as a reminder and also gives you some time to save work – or cancel the action itself.
All these settings can also be conveniently saved for later use.
Schedule your PC to be powered off any time you want with this fully featured tool.