Digsby (with clean installer) - IM, email and Social networks in one easy to use application.

In my opinion this is the best multi purpose communication application out there, but its popularity have decrease because it started to install a lot of junkware after build 38. I decided to do some searching and was able to find a clean installer.

Instant Messaging - digsby is a multiprotocol IM client that lets you chat with all your friends on AIM, MSN, Yahoo, ICQ, Google Talk, and Jabber with one simple to manage buddy list.

Email Notifications - digsby is an email notification tool that alerts you of new email and lets you perform actions such as 'Delete' or 'Report Spam' with just one click.

Social Networking - digsby is a social networking tool that alerts you of events like new messages and gives you a live Newsfeed of what your friends are up to.

Version 38 onwards is a stub installer that includes numerous toolbars etc.

Make sure you install digsby downloaded from the link you get here because it is a clean installer which does not have any numerous toolbars etc.