But don't forget Yahoo.Com,they are also provide service or tools to user like yahoo search.And if you don't know,Yahoo.Com also provide two more addition of the services to user for free!
As far as i knows,they has released Yahoo Messenger through the internet,Webmessenger and Upcoming,community for discovering and sharing events.
Webmessenger is a Yahoo messenger new version but web-based.So,you don't need install YM software in your pc or laptop to enable you chatting with your friends.
Upcoming is a community for discovering and sharing events. It can help you find stuff to do, discover what your friends are doing, or let you keep private events online for your own reference.