Imagine I have three Ubuntu computers home, laptop, beach-house. They all have the same version of Ubuntu, 10.04 installed, and are kept up to date from the repositories.

I use f-spot, thunderbird, and google-chrome on all of the computers. Is there a way to keep the data and configuration in sync across them, without requiring constant connectivity for normal (non-synchronous) usage?

For example, they should be usable without network connectivity, so something like NFS won't work.

An ideal solution would not require manual action to start the syncing process.