Actually, the Perl component is a per-user daemon on the client. The server (which I'm not directly responsible for) is PHP over Apache, with the idea that you could just throw it up on commodity shared hosting if you wanted to.

This is a final-year programming project we're doing for undergraduate computer science credit. The basic story is that our supervisor's office is across the hall from the university's IT guys, and one of the IT guys wants an "open-source Dropbox I could run from my own servers". He's giving us very free reign with the project; we're largely determining the system requirements ourselves. But I'm trying to define those requirements in such a way that this will be broadly usable.

I suppose if necessary we can actually ship/build a suitable perl with the client; that just seems a bit extreme...