This might sound a bit unusual, but I'd like to have a binocular finder. Practicality aside, I find I /see/ better with two eyes than with either one of them. And strangely enough, photography seems to require seeing.
On the more practical side, my left eye is just a bit worse than my right, and I'd love it if I could use my right. Anyone else here try to use their DSLRs with their right eye?