When I was researching for the first edition of my book Mac Kung Fu a few years ago I discovered an interesting new feature that, sadly, never made it into a final version of OS X. It was only in a beta release.
It required making a “defaults write” tweak to Finder’s settings pref file, and the key in question was FXDesktopEnableAutoExpose.
It was actually a pretty neat idea and I don’t really know why Apple decided not to use it.
Once enabled, Autoexpose meant that if you elastic band-selected any files on the desktop then the Show Desktop feature would activate automatically after a few seconds — all the program windows would slide off to the side of the screen, just like you’d hit the Show Desktop key (Cmd+F3, if you’re interested). You could then work with your desktop files. I can’t remember if cancelling the elastic band selection caused the windows to slide back in place, or whether you had to cancel Show Desktop manually. Like I said, this was a few years ago now, and there might’ve been more to the feature that I didn’t spot. After all, hacks like this don’t exactly come with instruction manuals.
Once upon a time there were a number of us out there in the Apple community who searched for “default write” hacks like this. They often got posted on the now-dead OS X Hints site, and the Secrets website. My book was full of the ones I found (some of which you know because people pretty much stole them shamelessly), and I wrote about the process of finding them for Pragmatic Bookshelf’s Magazine. Sadly, Apple’s tightened up OS X’s security and made finding these hacks much harder — and it was already a convoluted, time-consuming business.