To cut back on the time I spend idling in Internet Relay Chats, I uninstalled mIRC on both my notebook computers today. Wouldn't you know it, Trillian Pro has a fantastic IRC tool, with good color support, reconfigurable windows, and down-to-the-second logging (though I'm not sure whether this is such a blessing :-)).
In any case, if you like chat and want a great IM tool with a smallish footprint that handles many protocols (including AOL and Yahoo! instant messengers, ICQ, MSN - and now Jabber, it is said), get Trillian. Trillian Pro v2 is one of the best $25 shareware registrations (even better than PenguiNet v2 and LiveJournal, IMHO; I registered the former and will eventually register LJ, too).