GMail Drive

GMail Drive
From Wikipedia

GMail Drive is a free third-party namespace extension ("add-on") for Microsoft Windows. It allows a user to access a virtual drive stored in a Gmail e-mail account by causing the contents of the Gmail account to appear as a new network share on the user's workstation. In order to use this add-on, the user needs a Gmail e-mail account. The add-on enables the user to use the standard Windows desktop file copy and paste commands to transfer files to and from the Gmail account as if it was a drive on the user's computer.

Function
In order for GMail Drive to operate, the computer must be connected to the Internet and the user must have a Gmail account. A broadband connection is preferable though not necessary, as all operations are done though Gmail and consequently over the Internet. GMail Drive uses the inbox of the Gmail account to store files and creates a virtual filesystem on top of the Gmail account, enabling the user to save and retrieve files stored on the Gmail account directly from inside Windows Explorer. GMail Drive adds a new virtual drive to the computer under the My Computer folder, where the user can create new folders, copy and drag-and-drop files to, but does not give an actual drive letter, such as C:, preventing its use in all DOS applications, and some older Windows applications.
When the user creates a new file using GMail Drive, it generates an e-mail and posts it to the Gmail account's inbox. The e-mail appears in the normal Inbox folder when using the normal Gmail interface, and the file is attached as an e-mail attachment. GMail Drive periodically checks the mail account (using the Gmail search function) to see if new files have arrived and to rebuild the virtual drive's directory structures.
Multiple computers can connect to one Gmail account thus allowing GMail Drive to act as a multi-user file server.
Consequently, restrictions on the Gmail service are also enforced when using GMail Drive. For example, files larger than 20 MB cannot be uploaded, as the maximum file size of Gmail attachments is 20 MB[1]. In the past, Gmail also prevented users from transferring certain file types, such as an executable or ZIP archive. Some users bypassed this restriction by renaming the file extension or by putting it into a RAR or 7zip archive.

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