After reading Tal Leming’s fraction fever I decided to give this a go. I’ve long wanted to script a decent fraction feature, but couldn’t get it right. This is working perfectly (for now … I’ve only tested it in Indesign CS2 on Tiger). Click on the images to see it animated.
Still in progress … but Museo Sans will end up with nominators, denominators, superiors, inferiors, oldstyle figures (proportional & tabular) and lining figures (proportional & tabular).