Google's Native Client plugin

Google has released a new experimental browser plugin that allows web applications to securely run native code on the underlying platform. The plugin, which is called Native Client, is distributed under the open source BSD license and is designed to work with all major platforms and browsers.

Native Client provides a sandboxed web-embeddable runtime environment for portable x86 binaries. It also provides a bridge to facilitate communication between JavaScript and Native Client executables. This makes it possible for complex web applications to seamlessly leverage native code for processor-intensive computations.

i don't know about you all, but it scares me :)
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