I have begun to backup my movies in digital format. I am quickly discovering that I am in need of some type of server to easily store and access my files. I am looking for a cost effective way of doing this and my first thought was to use a Raspberri Pi to create a server. The tutorials I have viewed use external hard drives which are not very cost effective. Ideally I would like to have a computer case or hard drive enclosure that can have 3 or more hard drives. I would start off with one and add as needed. Is it possible to use multiple internal hard drives and connect them to a Pi?

If not, or if there are better ideas for NAS can you please share them? Thank you in advance!