Yahoo! Messenger 

Populate your friends list and enjoy one-on-one or group conversations. Communicate via text and audio or video calls. Add animated backgrounds, emojis, drawings and even games to your chats.

Yahoo! Messenger (YIM) is one of the oldest and most well-known instant messaging clients in the world. And its established reputation is largely well-deserved. Installing YIM on your computer you get almost everything you may want to get from an IM client: chat and chat rooms (large open chats similar to IRC channels), PC-to-PC and PC-to-Phone call functions, wide selection of available plug-ins, etc.

YIM is praised by many for its flexible stealth functions. If you are not in the mood or don't want to be disturbed by your friends or colleagues every two minutes, you can just login invisible to everyone and chat with some of them. If you don't want specific people to know you're on-line, just set the option to be invisible to them.

Another useful feature is the Yahoo! Messenger's SMS service. What everyone will definitely like about it is that it's free and quite comfortable to use. However, there's a small fly in the ointment: the SMS service is subject to a five-message limit. It means that you can't send more than five messages to a number till you get a reply from that number.

If you want to do more than just SMSing to mobile numbers you may want to sign up for Yahoo! Phone Out and make PC-to-Phone calls for an average of 2 cents per minute.

Apart from the above-mentioned features, the latest version of the program, the Yahoo! Messenger 11, has had some new ones added.

This brings us to another new major feature: Yahoo! Messenger is now available on mobiles as well and you can chat right on the go. In that way Yahoo! Messenger becomes a mighty social networking hub with a more apparent and intuitive interface and a larger number of features offered than that of, say, its Skype counterpart.

However, the client is not without drawbacks. The one worth mentioning is that you get bombed with loads of spam the very moment you enter a chat room. It looks like the chat rooms are not looked after very well. If you don't want to get ten dubious links per minute, you'd better use the conference feature, inviting your friends to chat at a particular time, thus avoiding annoying spambots.

All in all, Yahoo! Messenger 11 is one of the best existing instant messaging today, allowing you to create a large social networking hub within your client and chat with your contacts right on the go if you install it on your mobile device.