USB Hard Drive enclosures are now pretty cheap items compared to what they used to cost a few years ago when they became popular. For less than twenty bucks shipped, you can use one to store your old hard drive in.

Basically these devices allow you to put your old PC hard drive in it and still access your files through a USB connection. They are very useful when upgrading from an older PC to a newer one. It allows you access your files and data without setting up a network between the old PC and the new one or without having to install the second hard drive into the new system.

As a technician that has performed PC repair and data recovery for customers' systems, I find this an essential tool for any technician. Especially if the customers system has a broken optical drive. I can put all my tools and diagnostic software on the hard drive in the enclosure and access it through any USB port on the PC I'm working on. With a large enough hard drive, I can copy all the essential files from their PC onto the hard drive or even a full copy of their entire hard drive. Then I can reformat and reinstall their operating system for them, and when I am finished, copy back all of their original files for them. This is much faster than burning off a stack of DVDs or CDs, especially if their PC is having trouble with it's CD rom or operating system.

A new feature that some of the latest Wireless Routers are using is called “Network Attached Storage”. The wireless router will have a USB port on it. You can then use a USB Enclosure with your hard drive in it, and attach it to the wireless router's USB port. Now, any PC on your local network can access those files without your PC being turned on.

PROS – Gain quick access to your hard drive's data files on any PC or device with a USB port.
CONS – It is a separate device that requires a USB cable and an AC adapter to power itself.