Please visit the new Native Client SDK website for information on creating web apps that use Native Client to run portable native code securely in the browser.
Native Client is an open-source technology that allows you to build web applications that seamlessly execute native compiled code inside the browser. This Google Code project is for maintaining the Native Client implementation, including compiler and browser support. If you're writing a compiler, are interested in porting Native Client to a new browser, or are researching the security mechanisms underlying Native Client, you can find useful resources in this project.
Here are some other useful resources that provide background on Native Client: