Sahara Sync is a free software (as in AGPL) alternative to Dropbox. Eventually, this page will be supplanted by http://saharasync.net, but it's still under construction.
Sahara Sync is an AGPL-licensed alternative to Dropbox written in Perl. A client daemon running on a user's computer uses the host daemon's REST API to upload and download files, keeping things in sync. Eventually, Sahara Sync will support advanced plugins, and other features such as federation.
Not on CPAN yet!
No releases yet!