bootable microSD images, lockable flashdrive
Skip the CD set - most systems boot to USB and some don't even have optical drives anymore. Get a credit card sized holder for micro SD cards with bootable images of SpinRite, CloneZilla, Puppy, GParted, BackTrack, etc. and a USB micro SD card reader. You can create these images from an iso using netbootin. Also, I have a Kanguru lockable USB flashdrive to keep my tools from getting infected by the machines I'm fixing.
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