All the applications mentioned below are free and open source and can be customized to any taste you like. Each one has its own plus points and negative points, so choose wisely before you start using any of them. One key thing you need to keep in mind before you start using any of these messaging clients is that you wont be able to use the features each protocol offers to its fullest.
What I mean by that is, for example MSN has a feature where you can 'nudge' your friends if you're in a hurry to receive a reply. However with these messaging clients you'll need to install special plug-ins to do that before you can start chatting.
Trillian Basic (Windows Only, for now anyway) - This little application will allow you to chat on MSN, Yahoo IM, AIM, and even IRC with the least amount of configuration. It has a wide array of customizable skins and plug-ins that you can install quite easily. It's bigger brother Trillian Pro is a paid application but you'll most likely wont need the additional features if you're just going to use AIM or MSN. The upcoming version of Trillian, Trillian Astra has a host of other features and works on a Mac, iPhone and is accessible through a web-interface.
Adium (Mac Only) - Hands down the best multi-protocol application on a mac (even superior to its Windows twins for that matter). It can connect to pretty much any protocol out there and almost every little part of this application is tweakable. Take a look at Adium Xtras to get a glimpse of the customization options in this great application. If you're fortunate enough to be able to use a Mac as your computer, Adium should be your chat client.
Pidgin IM (Windows and Linux) - This is great for people who want to chat with everyone but don't really care about the look and customization abilities of their chat client. It supports
- Google Talk
If that's all you need then Pidgin IM is the choice for you. If you want to customize your chat client a little more you'll want to get Miranda.
Miranda IM - This is the ultimate small, lightweight, cuztomizable multi-protocol chat client if and only if you are ready to spend 30 minutes configuring the chat client. If you're comfortable with the default look and the default features of the application then you'll love this light weight client.
However, if you want the client to look a little better and function with several other protocols you'll have spend a lot of time in getting Miranda to behave the way you want it to. I personally find it a bit cumbersome to download a lot of plug-ins, many of which should have already been included in Miranda and wasting my time customizing it before I can even use it. But if you have a lot of time on your hands then Miranda is your best bet.
It works with AIM, MSN, Yahoo and ICQ. It can also work with Google talk and other protocols if you're willing to install the plug-in for it.
So there you have it. Now you can use 1 single application to reach out to thousands of people across the globe without having to use and configure a gazillion different applications.
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