External Hard Drive, Make one

I have always looked at those external hard drives and then looked away because of the cost. I have a couple 120 gig hard drives laying around that I do not use anymore or if you have old computers laying around you can take those drives out. Anyways you can make your own External Hard Drive by just buying a $19.99 enclosure, plug in the old hard drive and bingo External Hard Drive. You can get them for IDE or for Sata drives, ordered two for my 120 gig drives and will do a how to, it is always good to save money.