I was working along nicely on my Mac when it began freezing. Then it progressed to "booting, but not quite all the way" before it froze. Now it won't boot at all - the buttons are lighted, and I hear whirring and clicking, but the screen remains gray. I do not have any software CD's (lost them in the divorce). I do not have a CD burner to back up before I try something radical. I do not have a disk drive (lost that in the divorce, too). I love my Mac, and the local repair dudes make fun of me when I come in with it, so that is not an option. I've unplugged and replugged multiple times. Turned it on without extensions. It just gets worse. Any suggestions (other than jumping out the window)? TIA.