On Tuesday, February 10, 2009 Gmail Labs added a new feature by which you can add your Current Location to your Signature. Ok so i think Gmail has reduced one question that many people ask after reciving a mail is Where are you? or Where are you from?-in case of unknown Email address.
so to add your current location to your signature try this
1. Login to your Gmail account.
2. click on the link "Settings" in upper right corner.
3. Click on "Labs".
4. Scroll down to "Location in Signature" and check "Enable".
5. Then go to "Settings"->"General"
6. Scroll down to "Signature" and check "Append your location to the signature".
7. Reload and you are done.
Enjoy.