It's always good if you can learn from your own mistakes, even better if you can learn from someone else's. Now what follows might be a little obvious, but what caught me out is just how quickly something can go bad.
I have a Mac Mini in the lounge that's now doing sterling service running Plex Media Server 0.9.0.21. First up, if you haven't tried Plex, then this is what your Mac Mini, a TV and your video/music/photo collection were made for! Anyway, to get back on track the majority of my interaction with the Mac Mini and Plex is via the Apple Remote Control and I rarely have to use the keyboard or mouse. The keyboard is of course the all aluminium Apple Wireless Keyboard which came with my Mac Pro, but which I replaced with a Logitech diNovo 'Mac' keyboard as I find it both more comfortable and functional for heavy use on the Pro. The Wireless Keyboard was however fine for the occasional use it saw with the Mac Mini.
Cheap batteries - you get what you pay for!
I'd loaded it up with three Duracell Ultra AA batteries ages ago – can't even remember when – but inevitably I finally got the on-screen warning that the batteries were low and needed replacing. I only had two spare Duracell's so later that day I picked up some supermarket AA batteries while I was out shopping, and then popped the two Duracell batteries in, followed by a Sainsbury's Extra Long Life Alkaline battery and thought no more of it. Just four weeks later the low battery warning popped up again, so I went to remove the batteries to check. First problem was it was very difficult to remove the end cap from the battery compartment and as I did so I saw there was corrosion on it. Then I had a devil of a job removing the batteries, having to resort to hitting the keyboard on the carpet.
Luckily after about 5 minutes of careful bashing, all three batteries were out and I discovered that while the two Duracell batteries looked fine, the Sainsbury's battery had leaked. The top third of the inside of the battery compartment was covered in this greyish white corrosion, as was the battery itself! I then spent about an hour carefully cleaning as much of the corrosion out of the end of the battery compartment as I could using a selection of long pointy objects, an old toothbrush, a torch and a can of compressed air. Hopefully the keyboard has been saved, and needless to say the supermarket batteries are being returned and I'll stick with good quality batteries from now on!
If you're tempted to use cheap batteries with the Apple Wireless Keyboard, then just take care you don't suffer the same fate I did. Had I put the supermarket battery in first before the two Duracells rather than after them, then the keyboard would probably have been history.