Leopard arrived in the post last week and I set aside time to install it on my MBP this evening while watching the tennis. I install it, and it all goes grand...then i reboot. After the reboot, I get the chime, the grey screen with the logo, the little pinwheel spins around...and then a totally black screen. Cue a major freak out with lots of googling and searching all the mac support forums i can find. I ran the Hardware test, reset my pram...still nothing but darkness. I then start looking at for the opening times of my local Apple Store, and try to work my Monday around a trip there. I left my MBP alone and sat down defeated and worried... Then I booted it up one last time, with fingers crossed, to see if it might work. No dice. Then as I reached across to hit the power button, I accidentally tapped F12 and noticed a tiny flicker of very dark grey on the screen. It turns out that somehow the brightness of my display had been completely turned off. So crisis averted! Hence the LMAO in my post title. I would have felt so dumb if I'd brought it to the Store for the guys there to turn on the brightness...and I work with computers all the time!