If you travel frequently and if you would like the reader of your e-mail to know where you are mailing from there is quick and easy way to do so. You really don’t have to type You Name – Your city and state. Well I am not sure how many people will actually require it, never the less here is a interesting feature from google labs from google mail.
To try it, turn on Location in tab under Settings Signature from the Labs
Click Settings at the top of any Gmail page and add your signature.
You are done, now create a new mail and check your signature ;)
How google find out your location is based on your IP address. This might not be always accurate.