So, I left my MBP on and went out for a while and then came back and the screen was black, the sleep light was on (not pulsing), and the computer was unresponsive. I held down the power button and the computer briefly shut off, but the sleep light came right back on again. It sounds like the hard drive is spinning, but it doesn't seem to be doing anything else. The cd drive won't accept discs. The only way I can get it to turn all the way off is to unplug the computer and take out the battery. I've tried everything that the apple website suggests for a computer that won't turn on, but nothing works. Any suggestions?