The guys over at 24C3 just demoed a Wii hack that is set to provide native Wii homebrew in the near future (not running in GC mode, and with full access to all the Wii hardware!)
They were able to find encryption and decryption keys by doing full memory dumps at runtime over a custom serial interface. Using these keys, they were able to create a Wii 'game' that ran their own code (their demo happened to show live sensor/Wiimote information, amongst a few other things).
Read here and watch video here."
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