Lullaby is a portable minimalist lightweight (buzzword alert) Shutdown and Alarm timer for Windows.
It is pretty much feature complete and working, but only tested on my own machine. So if you encounter any problems, please let me know in the comments.
Not required. Extract into a folder and go!
Select your time by typing in the respective boundaries (Hours:Minutes:Seconds), or hold the mousebutton down in either and drag up and down. Select your action from the drop down menu and press start.
You can replace the Alarm.wav file with a wave file of your choice, but don't rename or remove it, as it might crash Lullaby.
You must have the Microsoft .net Framework 2.0 or greater installed to use Lullaby.