VisitorVille
VisitorVille, is a program that shows the usage of a website as a city in which visitors move around the buildings. It's like playing SimCity based on what's happening at your website. The program can track live usage, and can analyse your server logs to watch what happened earlier. Recently a free, limited, version was released and with it I'll be watching my own city to see what's happening. Will you be visiting?
Update: What I missed was that the free version doesn't do log file analysis. And that was just what I wanted to use it for...