SteamShutdown
Automatic shutdown after Steam downloads have finished.
What is it?
First program that uses actual Steam files which indicate directly what downloads are running.
It doesn't use any hack like tracking the hard drive or network usage.
So this is the first reliable program that shutdowns the PC as soon as all Steam downloads have finished.
Usage
SteamShutdown has no window. It's only an icon in the taskbar. Click it to see the menu.
FAQ
Q: Does this program needs to be run as administrator?
A: No. If the program works only when run with administrator privileges, it is either a bug or unexpected security settings on your system.