Mozilla now have their own bookmarks, passwords and history sync service
called Firefox Sync. It's installed by default in Firefox 4, and available as
an extension for other Firefox versions.
Although I don't think these services are a good idea, Firefox Sync seems a
better choice than some others. The security implementation appears to be
better and the data is kept on Mozilla servers, which is a non-profit.
Firefox 4 with Sync
http://www.mozilla.com/en-US/mobile/sync/
The extension is released under the Mozilla Public Licence v.1.1, not sure
that's compatible with the GPL:
https://addons.mozilla.org/en-US/mobile/addon/firefox-sync/
