WinMend Auto Shutdown is a straightforward free tool that will shut down, hibernate or log off a PC at a pre-defined time.
You can tell the program to take action in a specified number of hours or minutes, at a particular date and time, or daily at a certain time.
And when that time arrives, Auto Shutdown is able to shut down your PC, log off, or set it to sleep or hibernate.
There are some risks with this kind of utility, of course: if you're still around and using the PC at the time, then shutting it down could be, well, just a little inconvenient. So it's good to see that WinMend Auto Shutdown displays a 30 second countdown before it takes action, giving you time to cancel the operation, if appropriate.