Wojciech Purczynski and Michal Zalewski have an awesome paper on floating data storage. What they mean by that is storage of your data on the internet, but not in a conventional manner. They mean storing it on the wire, and in mail queues.
On a similar note I have been thinking about a pet linux shell project that would entail a perl script that migrated between (predefined) nodes using ssh, (and private keys etc). The trick is that the perl script would never get written to disk, it would copy itself directly into the remote perl processor! Now I just have to write it