It may sound like a wierd solution, but this kinda works like a NAS
I installed Raspbian, wich has SSH and FTP allready enabled/included in it.
I installed Apache for http connections but i did not put an 'index.html' file in /var/www so when I put file in a random file, it will show an index page with content instead of a webpage when i go to the designated IP (actually I linked http://roytamminga.nl
to it. If you go there you will see some maps and files, just like a NAS would show)
So when i want to upload something to my ''NAS'' or "Cloud", I simply open my FTP program of choice (I use FileZilla because it had a very user friendly interface) and put files in /var/www/ then it will be available for everyone that will go to the designated IP.
You can make folders with names (eg: a folder with your moms name and a folder with your best friends name) and put a file named .htacces in it. With that you can make users with passwords so only the ones with the credentials can login to that folder. Google htacces for more info.
If a file or folder is not accessible, you can SSH into your pi with Putty or a SSH client of choice to chmod the folders/files.
I hope this will help you with what you want!