Has anyone come across a mod that either has companions already running the NoM script so that they have to eat, drink and sleep like the PC, or a mod that adds this script to NPCs in the game that are in Follow Mode?

Nope -- I haven't. There's only one mod that I remember running across that has something along those lines, and that's because I'm currently working on revising it. In Razhkul's Reign of Fire, you must feed your dragon meat or it will suffer stat penalties and its disposition toward you will decrease, eventually resulting in a periodically-rolled chance of its rebelling against you (attacking you, and only stopping once you've reduced its health to some threshold). If you don't feed it within 6 days, it dies of starvation.

Kind of a simplified model, but then I think it would have to be. With NPC eating scripts, it'd be quite a lot more scripting overhead, and then you'd deal with food recognition issues. However, with one of the things on the drawing board for the revision of NoM to (as-yet-still-unauthorized) NoM 3.0 is the moving away from list-checking-based eating for the most part, and using "potion" foods (cooked meals that use the Alchemy framework in the game engine, rather than the Ingredient one). I imagine it would not be too difficult for someone to port over a simplified, stripped-down version of the NoM eating scripting for companions that tracks hunger, applies penalties (and issues complaints to the player), and that recognizes cooked meals (not raw ingredients, which would clearly be obnoxious), but I'm still learning a lot, so I'm not sure how feasible and desirable it would be to implement it. Probably not via implementation within the companion's main script -- that seems like it would be a mess -- but via a global script customized with the companion's ID.

It sounds very doable to me. I was thinking about this last week myself with my slave companion.

I was thinking about that as a possibility in a companion mod I'm working on, but I know very little about scripting.

You could do this with MWSE fairly seamlessly or without by using topics and dialog (would limit types of food).

Well let me know if you guys design it. I think this would be awesome. I'm playing with a companion and we ended up in an area heavily populated with Ashlanders. I couldn't find a way to get her out without us dying so I locked her into a cave and Almsivi'ed to the nearest town. It would be awesome if I had to keep warping back to her to keep her alive with food. Sure you can role play it, but that's not the same!

This would really be awesome if implemented.

Ugh. what happened with Mr. "I think this would be easy to do"? Why didn't he get his little modding butt back here with a link to the oh-so-doable-mod?

WAAAA!!!!