Randy posted on the idea in this Group buying business idea(s) thread...
http://www.sowpub.com/forum/showthread.php?p=27860

Dig more into Google using misc. Keywords and related phrases and you'll get Overwhelmed with ideas...
http://www.google.com/search?q=group...rmd=ivns&tbo=1
http://www.google.com/search?hl=en&c...&btnG= Search
http://www.google.ca/search?hl=en&cl...&btnG= Search

Hot off the Press! ...
http://news.google.com/news/more?hl=...ed=0CDwQqgIwAQ

Phil