Several companies (google, IBM etc.) are known to hire mathematicians with advanced degrees (Ph.D. and so) to work in different sectors; I mean mostly research oriented positions in industry but could be something else too. But I almost never find any such job advertisements in the standard mathjob sites I know of, including mathjobs.org, euro-math-soc.eu/jobs, nordic math jobs etc. Where can I find these type of job advertisements?
One of the best sources available now is the SIAM site:
This has quite a mix of jobs at various levels, but you will find research positions there as well.