Make money from file sharing site

A challenge will be legal problems, since what most people upload to these kinds of sites are illegal (copyrighted) files.

Of course, if you use a disclaimer that you do not take responsibility for what are uploaded and that people upload files on their own legal risk, then you should be just fine.

Now, I think file sharing sites have a double-edged sword, because we know what people want to upload and why, but we can still not appear as a business that we support this (aka uploading illegal files).

So, one thing that would distinguish (I think, I haven't researched so much on this, but I would imagine) your file sharing site from others, that would be appealing to most people is if you offer ANONYMOUS UPLOADING.

In other words, no one would know who uploaded what and private information such as IP and such would never be recorded on your servers.

This would appeal to many people because of NSA and such these days. As said, this is a double-edged sword and extremely sensitive to talk about so I won't suggest or recommend anything (everything I just said is a lie) ;-)