As the different companies involved in Instant Messaging are intent on not supporting each others standards, you have to look elsewhere to be able to use all the standards at once.

Easy Message is a clean looking client that supports AOL, ICQ, MSN and Yahoo! A useful extra feature is that Easy Message can monitor an email account and alert you when a new mail is received.

Setting up accounts is very easy, but there is no help included with the software should you get stuck.

With its tiny file size and its freeware status, there is no reason not to give this a try.