I just thought I'd share this with you. I've got no idea how many people already know this but I sure as hell didn't and it scared the bejeezus out of me. I was just surfing through the forums in Safari as per usual when I went to click on the desktop but I didn't realise I was still holding down ALT/OPTION. Where the hell did Safari go! Uh oh, I broke the 'puter. Apparently, OPTION clicking on the desktop will hide the currently open app, how cool is that! Sorry if it's obvious, I just thought I'd share.