Here are three amazing math, science and technology blogs that I think more people should read:
1. Understanding causality in economics and social science (e.g., People who go to college make more money than those who do not is this because college improves their subsequent performance or because people who are more likely to do well anyway tend to go to college?) is an obsessive interest of mine. Andrew Gelman is a statistics professor at Columbia, and his blog is the place to go on this topic. Killer post: What's the matter with Connecticut?
2. Somebody who starts a successful technology company is usually either smart or lucky. Somebody who does it twice is usually smart and lucky. Marc Andreessen is both, and his blog is a running commentary on how to succeed in the new economy. Killer post: Why there’s no such thing as Web 2.0.
3. The integration of genetics with evolutionary theory to create the Modern Synthesis plays the same role today that the integration of relativity and quantum mechanics did a half-century ago. Gene Expression is the place to go for a conversation about its social and political implications that is simultaneously highly technically informed and completely politically incorrect. Every time I go to this site I am offended by something and learn something. Killer post: 10 Questions for Heather Mac Donald.