Oooh, I just saw an Eleanor Burns Theater video (Jan 2013) that demonstrated a cutter that would substitute for a rotary- it's called the Sew Easy Ruler Cutter. She said it would be perfect for someone who was developing hand issues that would make rotary cutting dangerous. She even showed how it worked with her left arm laying across the ruler instead of pressing it down with her hand.
http://www.quiltinaday.com/shoponline/ruler/43419