desktopcouch stuff? (aka Ubuntu One)

[sabik]

DesktopCouch/CouchDB is a way to share data between (a) applications on one machine, and (b) several machines owned by one user. Both these aspects could be integrated with connectr; for instance, the data from the other applications (such as bookmarks or tomboy notes) could be shared with others using connectr. On the other hand, connectr could be used to synchronise machines (rather than UbuntuOne, which is a centralised service).

http://www.freedesktop.org/wiki/Specifications/desktopcouch

Note: on closer study, this bug will no doubt break up into a bunch of disparate features and will therefore have to be re-filed as multiple separate bugs.

[sabik (sabik)]

See also:
http://arstechnica.com/open-source/guides/2009/12/code-tutorial-make-your-application-sync-with-ubuntu-one.ars

Third way to integrate would be to make sure that a connectr identity can be synchronised over Ubuntu One.