Hi Jon, well I don't really know too much about NAS but the external storage tower only needs to be connected to one computer really so don't think I actually would need a NAS. But I could just be being ignorant and overlooking quite possibly a good solution.
However the link that has already been posted does seem exactly what I want. I just need a case to store all my IDE hard drives in them and then connect this tower to my PC. The only problem is with the type of connection to use; my PC is pretty old (only 1GHz) so not sure it would be able to handle much more than USB 2.0? But transferring via the ethernet connection could also be an option??