WinFS for Gmail, please

Markus told me about the new beta of Google Desktop (v3) which not only indexes your files, but uploads the index to Google so you can search your files from anywhere.

Of course, some people gave up on machine-local storage long ago, and Google already has their important files as Gmail attachments. Many businesspeople use their email client as a filesystem. Research students have inboxes full of PDFs sent by their supervisors and colleagues. These and other classes of users are perfectly happy having everything in email; their behaviour is in line with Danny O'Brien's discovery that "Everyone, including Alpha Geeks, use only one app".

Just add some WinFS-style options to Google Desktop, for sorting Gmail attachments by filetype by sender by month, and no-one would ever want to take files out of Gmail again.