Try this, From running Tiger push MacBook's power button. Press Shutdown, right after screen turns blue, close the lid. The white light in front will stay on without flashing. Flip the screen open, screen is black - yet your MacBook did not shut down, upon closing the lid - the light turn on again and MacBook is actually draining battery. My theory that during shut down process, closing the lid confused Tiger into going to sleep and that exposes the bug that prevents MacBook from waking up or shutting down. The only way to boot MacBook again, other than removing the battery, is to hold power button for 4 seconds and by that doing hard shut down. Any comments on this?