This app dumps to USB and SD: If an usb device is plugged in it will dump to usb. If no usb device is inserted it will dump to sd
To extract the dump you need your NAND AES KEY, you can get that by using Xyzzy. If you have runned xyzzy there is a file called keys.txt in the root of your sd card. Open it and look for NAND AES KEY. Now make a folder called keys in c:\ and open your favorite hex editor and copy the NAND AES CODE from keys.txt into your hex editor and save the file as nand-key.bin in the keys folder. Now just run "extract.exe" and select the nand-dump.img file and it will copy the .img file to the directory where the .exe is and extract it.