As a power computer user you surely leave your PC for some time to do certain tasks, be it audio/video processing, file sharing, or downloading. There is no way of knowing when your computer can go to sleep so the old school shutdown-no-matter-what programs are probably getting to you. In addition, many of those are either too simple or too complex for a power-off utility to do what it has to do. Smart Bomb PC Shutdown may be what you are looking for. It is a dynamic shutdown utility that will power-off your computer when needed.
At first glance Smart Bomb may look like a very simple utility. Maybe too simple? That's because it makes its own decision as to when the power-off has to occur.