I got a call, answered it (as I am applying for jobs all over and it has a local area code) - no one spoke, and hung up. When I called it back, it was a recorded message regarding selecting health insurance.
Have received several calls from this number, and many other unknown numbers, since I made health insurance inquiries on the web. Obviously, one of the insurers sells their call lists, probably to health insurance telemarketers. Wish I knew which one, so I could complain! I don't answer unfamiliar numbers, so good luck with that!