I've disabled all the common wakeup culprits (mouse, network, and USB activity waking up the computer), and while it has made things significantly better, I am

I've disabled all the common wakeup culprits (mouse, network, and USB activity waking up the computer), and while it has made things significantly better, I am still sometimes greeted in the morning by a powered on PC. And the wakeup log isn't helpful at all. It's driving me up the wall.