OSX Firewall question

yes and no. You cannot do it from the GUI, but you can access the firewall (ipfw) from terminal and add rules there to do whatever you want. I won't even go there, except to say that ipfw is the program you use from terminal...take a poke around google and read the man page about 100 times.

If you are worried about 'outbound' connections, then Little Snitch is fantastic and inexpensive (shareware.)

 

Yep what you are looking for is little snitch. google it or dl it on versiontracker.com