Interesting. This was something I was looking for just the other day ... sort of. I needed to transfer a file between two secure sites and that sort of thing can make traditional FTP really difficult. The file was encrypted but we didn't really want to sign up to some third party storage anyway. What I found was
HFS.
Their explanation is: "You can use HFS (HTTP File Server) to send and receive files. It's different from classic file sharing because it uses web technology to be more compatible with today's Internet. It also differs from classic web servers because it's very easy to use and runs "right out-of-the box". Access your remote files, over the network. It has been successfully tested with Wine under Linux."
Essentially it's a HTTP (web) server that runs as an application rather than a background service and it's easy to set-up to share one folder (or whatever) on a temporary basis while needed. Using http for transfer is not ideal but it has the advantage of using just one ip port, making it easy to punch a temporary hole through your firewall if/where needed. Combined with my
dyndns service this made it very easy to transfer some large files: no third parties have to hold the file, no size limits (except your upload/download limits).
Not for everyone, but it was just what I wanted.