This story comes from Littleton, MA, where TidBITS reader Nancy Kotary writes:

"Recently the weather here turned very cold (again!), and right about the same time, I noticed my 15-inch PowerBook G4 was acting up. I'd come home to find all sorts of weird windows open, or new folders on the Desktop with names like "ag899uiogheo". I was about to take it in for repairs when I accidentally discovered the cause: I'd been leaving the computer open, and my cat had taken to lying on the warm keyboard.

"I didn't have the heart to close the computer after that, and besides, it was sort of fun to see what sort of random havoc the cat would cause. Yesterday, though, I got surprise when I peered over the cat's curled-up form at the PowerBook screen and saw that Software Update was running and some huge download was in progress. It took four or five hours to complete, and when it was finished, it turned out to be the golden master installer image for Mac OS 10.4! I was able to burn the disk and install that same day - for free!"

Our conjecture is that there must be some secret combination of keys which causes Software Update to "see" the Mac OS X 10.4 installer as an available download. Perhaps this was put in as an Easter Egg (all this happened surprisingly close to Easter), or maybe it was just a convenient way for the Apple folks to obtain the latest build during development. There's no way to learn what combination of keys and buttons the cat may have pressed, so, like the Lost Chord, this feat of downloading a free Mac OS X 10.4 installer will probably never be repeated.