Google is testing a handy new feature for its web application of chat in the Gmail box of features. Users can SMS their existing Gmail chat contacts by opening a chat window and selecting the option to send an SMS. Once you enter their phone numbers, it will save the digits in your contact entries. This means that when those contacts go offline, the chat window will give you the option to switch to SMS. Usually, when you send an SMS from your computer to a phone, it shows up on the phone as a short code, or a super long number that changes all of the time. When you send an SMS from Google chat, you are assigned a unique phone number for every pair of Gmail user and phone contact. That means that every time you SMS a contact, that contact will see the same number.