A promotional tool named Google wave is an unfeasible idea and completely a successful one. The first thing you need to do is search for people who have the same interest as yours and your business, these people must be on social level. Secondly, look for a niche market which has the same idea of yours or within the same line of interest like yours. And lastly, increase the value of your customers by providing them enough information, this ia a way where you can provide target market of costumers which you would regularly need to pay lots of cash to get your hands on. That way, you can generate google wave cash.