nodeStorage brings simple S3-based storage to applications written in JS that run in the browser.

Dave Winer has an interesting thing going with nodeStorage.

nodeStorage is an open source project that brings simple S3-based storage to applications written in JavaScript that run in the browser. [...] All web apps need to be able to store information on behalf of the user. We've had a couple of different approaches to work with that don't require an identity system -- cookies and local storage. These are good but the data is bound to a machine, not to a person. So if you went to a different machine, you'd have to start over. —What is nodeStorage?

I'm a big fan of the idea (see my older post, "We need a new kind of web storage" for more thoughts on the subject).

I haven't played around with nodeStorage, but I intend to.