@naked | anyone else:
Nautilus File Browser >> File >> Connect To Server
Start Menu >> Places >> Connect To Server
Service type = Secure WebDAV (HTTPS)
Server = www.box.net
Port = [leave blank]
Folder = dav
User Name = [optional, log-in will prompt for it]
Name To Use For Connection = ["boxnet" or whatever label you prefer]
Like joakim2 had very mixed experience with above in Ubuntu Dapper/Power PC (G4). Had error with davfs2. Worked great with Kubuntu Dapper/Konqueror on same machine ... faster than Box.Net web access, split-pane interface, notifications ... suddenly a very useful service. Bookmarked. Used following to access:
Haven't used Box.Net long enough to comment on quality of service itself, but so far so good.
webdavs://box.net/dav [certificate throws error]
When I checked around a month or so ago, Box.Net looked like best free option in terms of space, access and single upload size.
Hope that helps ....