Syncing Options in Ubuntu

I have two computers (a desktop and a laptop) with ubuntu installed on them both which I'd like to sync. Right now I am using Dropbox and Ubuntu One (two cloud providers) two sync crucial documents but I need a better option to sync my entire hard drives: e.g, emails contained in Thunderbird, notes in Tomboy Notes, downloads, zotero files and notes, and everything else that one has on a computer. How can one do this? Do I do this over a network or a cable or what? I would appreciate any type of leads and tips.

Thanks much in advance!