Great Security Tool

myNetWatchman is a security aggregator that accepts data from firewalls throughout the Internet and reports possible intrusions and infections to the responsible system contact. Its a great service, and its free.

Even better, they offer a free utility called SecCheck for Windows machines. This can run either as an ActiveX control in the browser or from the command line. The command line generates a detailed file containing all sorts of useful information about running processes, network connections, and Windows configuration. Very, very helpful utility for trying to cleanup an infected Windows machine.