About 99% of the calls to my land line go to the answering machine. The message says "....you've reached this number. If this is the number you wanted to reach, well, we're not here...". If they don't leave a message, or a message that I feel I need to respond to, then it must not have been anything I needed to talk about in the first place.
I can't do any of the screening of overseas numbers or leaving answer-machine messages and hoping for the best. Many of the calls I do want to receive - calls from my family, and calls from my staff, my clients, and people helping me with research projects - are overseas calls, so I'd miss them if I didn't accept unidentified overseas calls. And many of my staff and people helping me with projects don't speak much (if any) English, so they'd get confused by an English-only answer-machine message, and everyone would get bored and overwhelmed by a bi- or tri-lingual answer-machine message. So my sexy voice* is my only option, unfortunately. * Not actually sexy.
Facebook *does* have a redeeming feature -- for me at least. I opened an account years ago for one purpose: to be able to login in quickly easily to forums where I occasionally post. All the automatic crap that happens as a result is opaque to me, since I otherwise ignore FB. As for Google+, I found it has a redeeming feature too: Hangouts is a nice chat client. With Google in general, I find their stable of free internet apps to be so fantastically useful that I do not begrudge their attempt to pigeon hole me for adverts. Twitter is for birds.