The Lomo Instant Square is light enough to operate with one hand, but I still needed to push the shutter button with my right arm. It wasn't too bad!
(I've got my right arm in a fancy support, but I can raise a cup of tea to my mouth, or reach up briefly to push a shutter button with one finger. When I was recovering from reconstructive surgery on my left arm back in 2007, I used an antique twin lens reflex camera with a waist-level viewfinder, which I hung from my neck: I only used my heavily-braced left arm to steady it. I see the difference now: the shutter controls are all set up for right-hand use! D'oh!)
