You would scare the crap out of yourself looking at all the hits on the port watcher! I log all occurences and IP address and look for patterns just in case.

That's why I like BlackICE Defender so much. It looks at each and every one of those hits and rates it using a very accurate threat-assesment engine. Then, if you see something that makes you worried, a single click on the "advICE" button shows you details about the threat and links to all of the necessary information such as the Microsoft patch to fix the vulnerability (if any).