I came across this handy application, and I think it'd be pretty useful for you guys who have GMail accounts!
GMail Drive is a Shell Namespace Extension that creates a virtual drive in the Windows Explorer, allowing you to use your Google GMail account as a storage medium.
It allows you to do basic file manipulation, such as copy and delete, on files inside the GMail folder. Because it is a Shell Extension, the interface you work in is Windows Explorer itself.
GMail files are physically stored as e-mails on your Google GMail account. The files are stored in mail attachments, and the filename and file information (such as filesize) is stored in the message subject line.
http://www.viksoe.dk/code/gmail.htm
Have fun you guys!