You could simply use an old computer lying around, install a Linux Distro on it and set up a few shared folders. There are only a few problems with this;
- The computer needs to be left on all the time
- It could create security issues for other parts of the network
- It can be unreliable.
The most important of these are that it could create security flaws for your network, if it is connected to the same router that your other computers are accessing. This can only happen if it is configured to be accessed outwith the network and by anyone in the world with a username and password to your server box.
There are server operating systems out there, like, for example, Windows Server, which is obviously paid version. All this is is a stripped down version of Windows, eliminating all the elements that could cause problems.
Ubuntu Server is a free, very popular Linux server distro which works much the same way as it's Windows counter-part does.
Alternatively, you could buy a NAS server. These can vary in price from as little as $50 without a drive right up to $10,000 without a drive.
I own a NAS drive with 2 terabytes of storage. I will hopefully be upgrading this to 4 terabytes soon. I use this as a central location for files, pictures, videos, music and other media that I own, which can then be accessed either by the Mac Finder, Windows Explorer or by a web FTP interface (or all of these).
My device has User and Group control with a limit of 15,000 users and 15,000 groups (obviously, I won't need all these).
If you have an old computer around, put a Linux distro on it, stick it on your network and use it as a file server. This is a good way to recycle old computers. If you have quite a few computers lying around, consider splitting them into things like
- Web Server
- File Server
- Media Server
- Email Server
- Maybe even a telecom/phone server.
If you have any other tips, feel free to pass them along.