On a PC and in need of another IM client? Try Digsby. Digsby is Freeware, multi platform, multi protocol, and the
most interesting feature I haven't seen anywhere else - an email management and social networking feed system.
support includes Gmail, Yahoo, MSN, but it also supports POP and IMAP.
The key feature though, is that you can preview your messages and
perform actions on them, right from Digsby. You can choose to mark mail
as read, report it as spam, or delete it among others.
social networking support includes Facebook, MySpace, and Twitter. It's only in beta now and there is not a mac version out yet. Check Digsby out!