what's running on port 8080?

I learned an important new unix command today: lsof. The name seems to stand for "list open files." The purpose of the command is to list information about the process who has opened a file. In unix-y OS's, sockets are file-ish, so lsof -i :8080 lists the process who opened the file named port 8080 on localhost, where ":8080" is interpreted as the address of a network file.
In my case, I traced the rogue 8080 to an instance of tomcat being started up by ~/Library/Caches/IntelliJIDEA70/tomcat_Unnamed_adomainahexid. I could tell from the domain name that this was a tomcat that I was developing with four months ago. Ouch.
I don't know why it was starting at system startup, but I'm not in the mood to dork around (anymore than I have already), so I rm -rf'd the cache directory and moved the tomcat install to apache-tomcat-6.0.18-hideme. It's gone now.