SD cards in two of my iMacs!!! I used two of the methods explained here and one of my own. First, I turned off the computers and firmly shook the iMac, with the cd drive facing the ground. For one computer I folded a piece of paper in half and taped one end, slid it into the cd drive and down and then briskly tugged on the paper and the sd card came flying out. On the second computer the paper would not work, so I took a thin, plastic ruler, angled it in from the top to the back-bottom corner and flicked the SD card out (not sure I recommend this method, but it worked). Good Luck!