I doubt there are plenty of others or we would hear more. I've had my N800 since March and I've never had an SD card issue. I have followed the advice of a few people on this site a got a couple Transcend 4gb cards (150 speed). Are you formatting them in your laptop? If so, how? What "rescue" utilities have you tried? By chance, do you have a Mac and a card reader you can use? I use Windows, Linux, and Mac OSX....I find that it's often easy to bring cards back from the dead with Disk Utility on a Mac or QTParted on Linux....(I use Ubuntu). You may also have a faulty card slot....is it the same slot each time or does it happen in both? Could it be the laptop or card reader if you're using one to load data?