This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
I just tried that though and it didn't seem to show me everything. As for blocking ports, that would be the job of firewall. I don't think that functionality is build into OSX, but I'm sure there are software firewalls available that you could install.