To be honest. I was curious to see one in person. Its very interesting how it happens. the sound skips and the black aero looking glass slowly comes down and BOOM! There it is... it tells you to restart. Anyway. My computer is almost 8 months old and I haven't seen one till now... I'm not worried about it. My computer started fine and works like it did before. But I was wondering what caused it and if it might happen again? I was using iMovie and importing a film. Some school work I'm finishing up. I had iTunes open and was listening to Stairway to heaven. And I was on a website with Safari. Do you think maybe I just had a lot going on? Thanks ^^''