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's a web service for campaigning against wars. We'll call it Iraq.tv.
"Sounds like a good idea to me"

Just what you were looking for.

It's a P2P service for writing books which relies heavily on RSS feeds and targets procrastinators. We'll call it RockText.
Idea created by Josh Sharp, who also makes real web applications for those with sensible ideas.
* success not guaranteed.