Want to cash in on the Web 2.0 craze but don't know how? Make a Web App has the perfect idea for you! Success 100% guaranteed!*
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It uses viral appeal to create a compelling site for groceries. We'll call it SinkGreen.
"Revenge Registry. Register the percieved wrong being avenged. One avenged, it is off limits. Benefit: reduction of cyclical revenge loops."

Just what you were looking for.

It's a vodcast on politics. We'll call it Campaignalizer.
Idea created by Josh Sharp, who also makes real web applications for those with sensible ideas.
* success not guaranteed.