I like this. Currently, webapps can read files from disk using an upload dialog and write them to disk by triggering a download, but this is clumsy enough that

I like this. Currently, webapps can read files from disk using an upload dialog and write them to disk by triggering a download, but this is clumsy enough that it only really works as an import/export feature. Webapps are essentially forced to have their "native" document storage be an online service, usually bespoke to that specific app. Files on my disk are files under my control. I can back them up myself, pay for their storage myself (rather than be subject to inflated cloud rates), and easily bring them to other web or native apps. Files hosted on my account on some website are... less so. If you're lucky, the storage costs are reasonable. If you're lucky, there's an API. Often there isn't.