I don’t know how much help internet does to business to grow but it certainly comes up with some superb concepts like this one as in the buyasone.com.
Basic idea is that if there are multiple orders you can get some discount so they have made some slabs for a given period like if there are 5 users you get 5 % off and say 10 users 10% and more than 10 you get 15% off as the no. of buyers increase you get more discount.
It looks really good on face but how much practical I am not too sure because normally it will be Electronic and house hold items and in such shopping you normally get a good bargain from the retailers so I think to improvise concept they should give some more discount.