Work for companies that are weak in what you're strong in, but strong in lots of other areas.
When I joined Google Search, I was frequently the smartest guy in the room when it came to JavaScript quirks, or web development, or rich AJAX apps. I was usually the dumbest when it came to massively distributed systems, or information retrieval, or i18n and accessibility, or unstructured data mining.
Over time, I've transferred a bunch of my frontend knowledge to other engineers, and I've learned a whole lot about how massive software systems are architected. I'm a better developer, the people around me are better developers, the company is several hundred million dollars richer, and everybody wins.