Easiest storage backend to setup/install

I meant a backend software. I could use FTP, but I will have to open 2 ports, setup authentication, and FTP is a bit harder to proxy that HTTP.

I would like to have something like this tiny webserver (TinyWeb) but with support for WEBDAV. This thing weight only 54kb. It just lack WEBDAV support.

I need to replace crashplan to backup to some relatives computer.