From the author's site (translated by Google):
With the small timer tool Sweet Dreams, you can reduce the volume of your PC in a desired time on the set level. This tool is so perfect for those who like to listen to music before falling asleep or watching a movie. Of course, this program can turn off the monitor after the specified time, shut down the computer or put it into Standby or Hibernation mode.
Advantages: Want to sleep while listening to music? I tested a number of plug-ins for Winamp, and also separate software. The search is over. This program is
very small,
no installation required,
freeware. It will
slowly lower the volume of your PC (not only of Winamp) at a rate you specify. Optionally, in the end it will either
turn off the monitor, shut down the PC, hibernate it, or put it in standby mode. And when you return it
prompts you if you want to return the PC to the original volume.
No disadvantages!