GMail Drive - Use the 3 GB space as ur Local HD

GMail Drive
It's a Shell Namespace Extension that creates a virtual filesystem around your Google Gmail account, allowing you to use Gmail as a storage medium. It drops the 3 gigabytes of storage allotted to your Gmail account right onto your desktop and looks & feels just like a regular hard drive albeit a bit slower because it's networked rather than local. Point your browser at http://www.viksoe.dk/code/gmail.htm, scroll down to the Download Files section, and grab a copy of GMail Drive. Unzip the installer and double-click the Setup icon. A few moments later, you should see a brand-spanking-new GMail Drive under My Computer in Windows Explorer. Enter your Gmail username and password and click the OK button to log in. A few seconds later, your drive will be ready to use. Merrily drag and drop files to and fro between your local drive and GMail Drive

As you add folders and documents to the drive, they show up as messages in your Gmail Inbox the GMAILFS: prefix appears in the subject of each message, along with the folder, filename, and file size. The file itself is stored as an attachment to the message.