I installed Leopard a few days ago on my MBP C2D and twice I've seen my computer crash during sleep. I put it to sleep and go do something else, and when I return it looks like it's not runningsleep light is off, the only thing noticeable is the fan running very quietly. It does not respond to the keyboard or power switch for about a minute, and then I'm able to force shut down with the power switch and reboot. It doesn't always do this, just twice so far. I wondered if anyone else has heard of this happening.