WiiND v2 for Nintendo Wii Released, Now with USB 2.0 Support
This app dumps the NAND to USB and SD. Before you can use USB 2.0 you have to install the "modded" version of the USB 2.0 cIOS (cIOS rev7 + USB 2.0), don't worry it, won't overwrite anything, it installs as IOS222.
To extract the dump you need your NAND AES KEY, you can get that by using the "Key Grabber" included it's xyzzy but it dumps nand-key.bin and common-key.bin to sd card. When you run the program there will be a nand-key .bin in the sd card (also a common-key but that's not necessary for unpacking but can be useful for other things ;))
Copy the nand-key.bin to c:keys (make the folder keys on your c drive if it doesn't exist) and then just run "extract.exe" and select the nand-dump.img file. It will copy the nand.img to the folder where extract.exe is and extract it!