From Dorai's Learnlog
Blogs are a great source of ideas. Some of the bloggers are the smartest people I know. They comment about products. They track trends. They predict future products. They compare and categorize. And they share it all free.
So how about mining ideas from blogs? And using them to improve your products, projects. For example if you look at a list of mashups, you will certainly get ideas for other mashups. If you enjoy using Web 2.0 products, you already know a specific user interface you like. By tracking the most popular Web 2.0 products, you are getting some free market research.
All these are talked about in the blogosphere.