Last night I was watching a trailer on the Apple site, when I got a spinning beachball, my system became none-responsive, so I turned off my iMac from the power on the back of the system, but now my system won't allow me to log in. Everytime I start up the computer, I just get a folder icon with a flashing question mark. I have tried the following to solve the problems, but nothing has help. 1. I have tried holding down the alt key and turning on the computer, (so I can select the start up disk, but it won't see any start up disks). 2. I have run an extended Hardware test off the Apple CD that came with the computer, and it has found no faults. 3. I have run system profiler off the CD and my HardDrive is not showing up. 4. I have zapped the P RAM, by holding down Alt, Apple, P and R when starting up the computer. Does anyone have anymore suggestions? I would be VERY grateful.