You didn't get a chance to check out the Unreal Tournament 2004 X-Fi Patch? You don't have a X-Fi card installed in your PC yet? If so, here is something that might be interesting for you. A video showing some of the features which came with the update from Creative.
"This is a video I made comparing the normal audio vs the X-fi patch which came out recently. Also shows some of the more nifty features, like the musical accents mode."
X-Fi Zone
X-Fi Zone