I saw this in a couple of places but I’m going to take the description from kevinrose.com since it explains it really well:
“Turn your GMail account into a 1GB of off-site storage:
GMail Drive is a Shell Namespace Extension that creates a virtual filesystem around your Google GMail account, allowing you to use GMail as a storage medium.
GMail Drive creates a virtual filesystem on top of your Google GMail account and enables you to save and retrieve files stored on your GMail account directly from inside Windows Explorer. GMail Drive literally adds a new drive to your computer under the My Computer folder, where you can create new folders, copy and drag’n’drop files to.
This is a great way to backup your important docs. The only downside is that it’s limited to 10MB per file (the GMail attachement limit). Hopefully future versions will break up large files, then upload.”
UPDATE: I just got around to trying this out and I must say, this is an awesome feature of Gmail! It’ll be interesting to see if Gmail does anything to stop it. There is the downside of the attachment limit, but I can see this being great for people that use a computer at home and at work and want to be able to move files back and forth very easily. Just install Gmail drive on both computers and you’re good to go. You can choose to have it log you in automatically or not, which makes it possible for multiple users to use the program from the same computer. Very cool!
UPDATE 2: I’ve also set up a filter within Gmail to automatically label any email that starts with GMAILFS (the header for all Gmail drive files) to be labeled as GMAILFS and automatically be sent to the archive. That way, when I’m actually using Gmail, I don’t see all the files that I’m storing with the Gmail drive in my Inbox – give it a try!