So I just returned from a photo shoot in the caribbean and I took oogles of photos with my Nikon D40. This morning I took the SD and placed it into my card reader which initially read the card but as I clicked into file folder of the card my Mac gave me the slow cascading black screen followed by "Please Restart Your Computer". Now, after restarting the computer, the SD card is showing up as "Disk Unreadable". Some please tell me this has happened to them before and they were able to recover files. We're talking hundreds of photos ... Help.