I'm willing to bet that many of you are the designated IT person in your home, dorm, or small office. My wife calls me her personal IT dude, and feigns sympathy that I don't have an IT person of my own. She can turn to me when she's stuck, but when I look behind me, I see that I'm the end of the line. (Anyone feeling sorry for me yet?)
Courtesy of SanDisk
Anyway, if you're the IT person in your group, one of the best things you can have in your toolkit is a USB drive loaded with a bootable copy of the version of OS X that you use. Even better, keep several bootable flash drives on hand; they're inexpensive and you may need more than one version of OS X.
On each drive, have a ready-to-clone version of the OS that you can boot from, as well as your favorite troubleshooting tools. OS X comes with its own set of troubleshooting tools, including Disk Utility, Terminal, and Activity Monitor. I like to add a few other items, such as disk cloning tools, drive repair tools, and lists of helpful web sites; anything that can help diagnose a problem.
The key to all of this is creating a bootable USB drive. We have guides that will take you though the process for various versions of OS X.
The first guide covers creating a bootable USB flash drive for OS X 10.5 (Leopard) and later. This guide will work for any Mac that can be booted from its USB port (Intel Macs only).
You may need to make multiple bootable USB flash drives, since Macs can usually only boot from the version of OS X they came with (or a later version). You won't be able to boot your new MacBook Pro, which came with Mountain Lion, from a USB drive loaded with Snow Leopard. Take inventory and figure out how many USB flash drives you need and which versions of OS X. If all of your Macs can run the latest version of OS X, then you'll only need to create one bootable USB drive for troubleshooting. Many of us also have older Macs, though, so it's likely that you'll need to create at least two bootable drives, with different versions of OS X.
The guides at the links below will show you how to create Lion and Mountain Lion bootable Recovery drives on a USB flash drive. While Recovery drives won't let install your own favorite troubleshooting tools, they will help you download a new copy of the OS if you need to reinstall it.
So, go grab some USB flash drives and create your own bootable troubleshooting arsenal.