PUBLIC MARKS from vista with tags mashup & business

Paul Rademacher talked about how Housing Maps, which is a mash-up of Google Maps and craigslist, came out of a real world need for him and grew from that. The lesson here is that usefulness is a key driver for success in the Web mash-ups world. He also mentioned that Housing Maps isn't necessarily a pure API mash-up, because the craigslist data is taken from their RSS feeds and then he stores the content on his own server. So mash-ups are still painful to implement, despite all the hype around using APIs to deliver them. Paul also said he that reached 900,000 visitors to Housing Maps without any marketing effort, which is an indication of how mash-ups can be low-cost to both produce and market.

Developing a mashup can be a lot of fun and it's usually low cost, because you're using (semi) open tools and data. Forget fun though for a minute - is there a business in mashups? There are obvious benefits for the data providers, for example both Google and craigslist benefit from increased traffic to their sites. In most cases that leads to increased revenue as well. But what's in it for the mashup developer, apart from publicity and prestige?