The language itself is trivial to learn, the environment COBOL is running in is usually the challenge. I really enjoy bug fixing existing software, and I enjoy learning about existing systems. As I said I am done with working for myself, and as for the social aspect, I'd find it interesting to work with peers who may be closer to my age, and not a group who is just starting in the game working on their first big piece of software. I was there 30 years ago, this seems an opportunity to work with more mature and experienced folk. Also back in the day there were far more women working in software than there are now, there may be more gender balance in the older technologies.