If you have an extra hard drive, no reason not to use it in this manner, these things are a great idea for mass storage.
I just went through this same thing not to long ago, here was my experience setting it up. Note, I know the one I got from Best Buy was expensive, around $50, but I got it because I wanted to get it all done in a day, because of my schedule, didn't feel like waiting for delivery, etc.. Here's the thread I posted on it.
http://www.linuxquestions.org/questi...d.php?t=496456
I bought the Best Buy model(Dynex), and as I mentioned, its expensive compared to the ones I see online at Tigerdirect.com and Newegg.com . I have no experience with the ones below, but they are a couple of the higher rated enclosures for 3.5in drives.
http://www.tigerdirect.com/applicati...600952&CatId=0
http://www.newegg.com/Product/Produc...82E16817146601
I really like the one I got from Best Buy, but I suspect any of them will work just as well.
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