There is loads of work out there for architectural cad technicians (like me) but unless you are capable of running a job as well then its not fantastically well paid. Good techs get at max £30k.
I do a bit of 3D in adition to my normal 2D work.
The attached file is something i did for a presentation a while ago. I've got a lot better since then!
3D pays more but fewer practices have 3D only people.
I dont know about other industries.