When nandroid does a back-up, it does not error out or warn if the card runs out of space. It will go through all of the back up steps and even produce an MD5 parity check, but it is checking the file created- NOT the actual targeted files as part of its verification process (only the parity of the final file created). I discovered this (almost) the hard way, but noticed that my card showed zero space. The back-up should have been about 850mb, but was 395mb. I removed some files from my sd card and repeated the process and then did a titanium back up of apps. Shortly after backing up, I tried to install the King #2 kernel and my Inc got stuck in a boot loop. Had I not caught the Nandroid back-up issue, I would have been in a rough situation. The sad thing is I have a 32gb card, but is loaded with PSX games, other game roms and MP3's. Even without this stuff and a smaller card, several nandroid back-ups can accumulate and take up more space than you expect. added: I am not sure if Titanium also does not verify the targeted files after a back-up. In summary: Check you card for space before backing up stuff!