Anyone and everyone who uses both thumbs for backspace is scary. :O

Space: Right thumb
Backspace: Right ring finger
Shift: Left Pinky.

My left ring finger takes over my pinky's capital letters. :o I can't really hit the right Shift key without moving my hand, so I never use it. It's also terribly difficult to use any other finger for space as my right thumb still bats away at it anyway. Wow, I just realized my left thumb moves around espcially when hitting period.