Hacker by the name of GodzIvan came up with this diagram which simply write protects the NAND flash in the Xbox 360 by connecting WP to ground pin (if the flash type has different pinout, just find the datasheet to locate WP). This modification does not stop the ban from Microsoft, but it prevents deletion of the HD installation certificates required by games which means you can still install them on the hard drive. In order to update the kernel this mod must be disabled.

Another day another hack for the 360 it seems these days.