Some interesting information about what can potentially be done with your IP address by Mr. Bad guy. There is also a quick scan of your ports to inform you how visible or vulnerable on the internet you are. Check it out at Gibson research
. This guy is a pretty interesting fellow and has had his share of evil done against him by denial of service attacks, hacks, and other stuff. There are other tools that he wrote to turn off loopholes in software that windows has active by default.