Free Website Stats - Visitor trackers and hit counters

Statisfy - Free Website Counter: I haven't tried this one yet but the features look great! This comprehensive statistical tool has real time stats like "Who's online", how they got to your site (keyword tracking, referrer information) and even AdSense tracking.. and it's totally free! No ads on your website and the tracker itself is invisible.
Free Live Help, Chat and Visitor Tracking: Add 100% free live help chat and real time visitor tracking to your website. Unlimited operators and departments. Looks like a very helpfull and unique service that both webmasters and visitors will appreciate.
Bravenet's Counter / Site Stats: They offer a free counter / tracker combo. The counter image is very customizable. The stats package includes page views, unique visitors, first-time visitors and returning visitors. a few other handy statisitcs are browser statistics like screen resolution, color depth, browser and operating system.
Stat Logger Website Statistics: Free invisible stats of your website traffic, very easy to install, just sign up then copy and paste the code into your page. A few of the best features are: password protected statistics, referrer, search engine and OS statistics, and more, all in real time reporting.
StatCounter: This free, invisible webpage trackers shows a lot of information about your visitors. A few stats included are pageloads, unique and first-time visitors, which pages are popular, referrers, search engine and keyword analyis. A unique feature is the ability to "zoom in on your visitors' locations and watch in real-time as they navigate through your website". Private or public stats.. your choice.