Service that negotiates and switches between companies on your behalf.
answerly: It seems like a valuable service and has a built in revenue model in that users could pay a fee based on the actual savings that they realize.  There are two questions/issues that come to mind:1) How wold the negotiations be facilitated?  My guess is that this would have to be actual human-to-human contact, which seems expensive.  One way to keep the costs down may be to develop a filtering system that only accepts users with bills that have a high likelihood of being eligible for some discount.  That way your resources would only be spent on the users most likely to generate revenue for you.2) Do service providers like cell phone companies discuss account details with a third party who is not the account holder?  It seems like the type of thing that a big company wouldn't want to allow for any number of reasons (i.e. privacy concerns, preventing an "agent" from negotiating on behalf of the user).Some aspects of your idea are topically similar to BillShrink.com although they aren't doing any negotiating on behalf of individual users.  They are doing quite well.