What I was trying to say in the pub, but perhaps needed to be written down instead, is that many of our ideas are quite far-reaching, but perhaps the idea of having _one_ unusual escape character with the shell, with or without special keys/graphics to indicate it, would be a comparatively superficial change to an existing shell, and might be worth trying as an experiment -- I've never implemented a shell in any way, and probably won't try this one, but someone more confident might well be able to do so without too extensive a modification of an existing one...?