If you live in US, Canada or India now you can send SMS to your friends and if they reply you ll get via your
Messenger 
Another update is they added local language versions for Thailand and Indonesia and 9 new languages for the Indian version ( geez how many language you have guys 
) to chose one of your language just log in to Yahoo! web Messenger India , start to chat with a friend and choose one of the Indian language from the drop down menu.
Didn’t try web Messenger yet ? shame on you go Try Yahoo! Messenger for the web now.