Remember the iPod classic? That chunky little slab of plastic in which you could store thousands of songs on an internal hard disk drive? Well, if you do, and if you still happen to have one laying around somewhere collecting dust, Chris Breen over at Macworld has the perfect job for it: using an iPod classic as a bootable emergency drive.
This isn't a new trick by any means. I still have my old 4th-generation iPod within arm's reach in case I need to boot a Firewire-equipped Mac, and I even wrote about this in my now-obsolete 2007 ebook "Take Control of Your iPod: Beyond the Music." But Breen and the crew at Macworld have updated the process for the USB-equipped iPod classic, with a few caveats thrown in for good measure. First, since the iPod classic isn't vented, it can get hot if you keep it hooked up as an external drive for a while. Second, it's slow, so your boot times aren't going to be exactly speedy.
Breen points to another post by his Macworld cohort Dan Frakes in which the latter blogger shows how to install Mountain Lion on a bootable external disk. It's a bit of work, but if you have an iPod classic that's no longer being used, at least you can give it a job to do in case of emergency.