I wish I could mod you up more. I am a big foss fan boy (can see by my nick), but most people don't care about licensing, if the code is open or not, etc.
They want something that works and fit their needs. That's it.
Cool stuff. I have been using Sucuri's Network Integrity monitor for the same thing... I monitor my own sites and some pages that I am interested to be notified when they change.
That can be very useful as an intrusion detection system if your pages are modified without you knowing it.