I was revisiting all of my printed web pages (they pile up after a while!).  I have been disposing of the paper by saving the web pages (when I can still find them) as Web Archive files (*.MHT) (You should really consider using this format for archiving your web pages if you use Internet Explorer).

Anyway, I ran across an excellent example of the XAG principle at work.  Spirit and Homes is a real estate referral service that uses participating real estate professionals to buy or sell your home.  Part of the agent's commission is donated to missions work.  This effort is affiliated with Project Referral and represents another normally commercial venture modified slightly to fuel the work of the Kingdom.  More information is available in a FAQ document on the Spirit and Homes website.