I’ve been evaluating Urchin, a web traffic reporting tool, for several clients. Everybody I’ve showed the output to has been impressed: it’s flexible, uses its own database, lets you look at reports and graphs over different periods of time, and has a nice little e-commerce revenue reporting system built in. You can download a trial copy.
Urchin was later purchased by Google, and evolved into what we now know as Google Analytics.
The “UTM codes” that are more so prevalent are, in fact, Urchin Traffic Monitoring codes.