Am I the only one who would pick Delta 100 in 4x5? I spent the summer contact printing cyanotypes in 4x5 and just loved those negatives. Now, for a camera, it would have to be one that I don't actually own right now. I do bravely cart my next-to-indestructable cc400 around in the field, but for a desert island I'd want something a little more portable.
Now, if I wanted to be found, it would be my Rolleiflex 3.5f. Every time I take it out of the case somebody comes up and tells me their uncle had one.