You can also mount nfs and cifs shares with Wizard Mounter and just use the file manager to copy files on and off the n900.

I use KDE and so have my n900 file system mounted via ssh/scp as a folder too. You can do the same with Windows.

I use rsync to synchronise any music, video, or other folders I want on my n900.

I use dropbox to get and recieve files from the "cloud".

If you can tell us more about what you want to do we can provide more options.