I take it one more step. I have Caller-ID, but I have not enabled voicemail on my land line (I do use it on my cell-phone, which is unlisted).
I will not answer a call from a number I don't know, period. Of course, that includes 800 numbers, and anything which reads "unknown caller" or "number blocked" on the Caller-ID display.
When I leave my house, upon return, I'll scroll through the Caller-ID record, and return the calls of folks I know. But really, anyone who knows me knows my mobile number, and they've figured out that they have a better chance of reaching me if they call there.
Caller-ID, when used logically, is a great invention. Would you open your front door without looking to see who is knocking? If so, why on earth would anyone answer an anonymous phone call?
I spend half my day at work on the phone, for the most part I don’t speak to anyone when I’m at home.
My cell phone is actually under my business name. And it is on the telemarketer do not call list. Since my business involves a lot of emergency technical support for refineries, pipelines, and utilities, I have another way of getting repeat offenders of the do not call list. They get dunned for one full day of services (at field service emergency call out rate). It is NOT cheap!