My Powerbook was making some funny noises. I thought it was the DVD drive at first, so I put a DVD in and it played fine. Then everything started slowing down and applications wouldn't quit. So I shut the computer down. When I restart now, it just goes to a blank gray screen for a minute or so, and then a little folder comes up in the middle of screen and it alternates between a "?" and the finder icon. Does this mean my harddrive crashed? Please say it ain't so.