I usually switch all my computers off during the night, except previous Windows boxes which I used as servers. These days the Macbook Pro is to all intents and purposes my main machine and sometimes, I can leave it doing stuff overnight. It's hooked up to a 23" ACD and a USB mouse/keyboard, and external drives both USB and Firewire. I used to have it in a lid-open configuration for a dual monitor setup, but I realised I don't like looking at two dissimilar screens for a dual-monitor system so I now use it lid-closed. If I'm around and I leave it for an hour or so, I can come back and hit the spacebar, whatever and it will wake up. If I leave it overnight it fails to wake up. I can press keys, tweak mice, open and shut the case etc but nothing works and I can only shut it down by holding down the power button. Could someone tell me the root cause of this and how I can solve it?