Audio timer, does anybody use one?

So I have a stereo in my bedroom and I listen to it every night to go to sleep to. Unfortunately, after the music stops playing, the stereo remains on until I wake up sometime in the middle of the night and turn it off while I am up.

My old Army buddy had a timer in his stereo, I never thought much about it. Seems like this would be perfect for me so I could listen to music and the timer would shut the stereo off after a while.

It does not seem to be a very popular item though and I guess nobody makes them anymore. So I have been searching for them and the only ones available anymore are "vintage" timers.

Can anybody recommend a decent timer? Does it seem like a bad idea to have an external device control the power going to the stereo? Is it harmful to the stereo to have the power yanked out from under it by the timer when it shuts the stereo off?