Cheat Engine

[oib111]

Is there any program for windows that will automatically shutdown your computer at a specific time?

[atom0s]

Windows Task Scheduler

Control Panel -> Scheduled Tasks -> Add Scheduled Task

[Labyrnth]

You can do this with a batch file or a small shortcut to your shutdown.exe with a modified target line also.
"-t " for time.. "-s" for shutdown.
http://www.pcmag.com/article2/0,1759,156438,00.asp

But Wiccaans method is better.

[atom0s]

Well if you wish to have options for the shutdown you can create a batch file and point the scheduler to that instead.