Instead of buying one of the big 40 GB or 100 GB portable usb drives on the market from seagate, etc...I wanted to build one by buying an internal drive for a laptop and put it in a steel casing since it would be cheaper. Also the internal drive would have a 3-5 year warranty against the 1 year warranty for above products. I wanted to ask other people on here about pros and cons?? This is a sample description I got on Amazon...However, for the same price (if you select 120GB) or even cheaper (if you choose 100GB) you can purchase a very small internal notebook hard drive (ATA6 or other suitable interface) and aluminum enclosure (supplied with USB cable, slim carrying case, and screwdriver set), put it together and make a perfect portable external hard drive. This will be definitely smaller in size and a more strategic investment. If you purchase the notebook hard drive, which is compatible with your laptop's interface, one day you may just upgrade your notebook. Otherwise, I think Seagate put inside a proprietary hard drive, which is can't be used for your computer upgrade needs. Also, internal notebook hard drives are usually provided by 3-year warranty and some even by 5-year (Seagate Momentus hard drive) but Seagate provides you only with a 1-year warranty, so keep that in mind as well. Won't you be sorry for your purchase if the drive crashes after a year of use losing all your data and invested money? So please reply!!