none
Non chess skills learned in chess

Critical thinking. Not to rush to judgement. Therefore I like correspondence chess more. Since time is not a factor it is the truly the place where ideas fight.

I got a lot of practice sitting in one place and concentrating on one thing for long periods of time. Also, as with any self study, I also got a lot of practice evaluating how well I was learning and devising techniques to resolve any problems either with the material itself or with my learning process in general.
Tournament play in particular I think made me a much better test taker... I've heard adults who go back to school can struggle with tests, but I think my test taking skills had actually improved! For example I was focused on accuracy not speed. I was often the last to turn in my test, and very often used all the allotted time. I also often took my tests twice (when possible), looking for every possible error I could have made.
Whether these were mainly part of my personality and would have happened with any hobby is hard to say. I tend to believe the only skills unique to chess are the chess skills themselves. Any activity where you earnestly work to improve yourself each day will help you build useful life skills.
what do you think?