I tried dumping my SD780 using Cardtricks 144, trying NewDryOS, DryOS, and VxWorks. Each one said "card locked" when tried several times in the camera, removing the battery for different amounts of time.
As another user said, when you open the battery/card cover, the camera turns off (hidden switch somewhere).
Also, when I format the card and install NewDryOS using Cardtricks 144, I don't see anything on the card using windows explorer. I'm not sure if its installed on a hidden partition, but I wanted to point that out. Cardtricks says it was successful in both formatting and copying the different operating systems onto the card.
I used a Lexar 128mb card formatted to fat16, and a USB SD card reader. I should also note that the "make bootable" button was always grayed out, even after installing the different OS's. Picture of cardtricks after NewDryOS was installed - http://i44.tinypic.com/15dlv6h.png
Has anyone else had any luck, or know anything else I can try?