Practical /Prog/ Challenge

The challenge is to make a PROGWATCH program

What it does is, scans this file:
http://dis.4chan.org/prog/subject.txt
every 1 min, 10 mins or 30 seconds or so..

When a change occurs (e.g. someone makes a new post or whatever) then it should exec some program set by the user, with the given args

so for example, you could set it up to open your webbrowser for  the page, or get growl to display "New thread on /prog/, title: Ive read SICP!" etc etc

I will post mine afterwards.. anyway good luck and GO FOR IT!

more like
while true; do cp prog.txt prog2.txt && curl -o prog.txt http://dis.4chan.org/prog/subject.txt && diff prog* | grep "^<" ; done