I don't own any kind of mobile device, and many, many times in my life have I gotten the raised eyebrows with a puzzled "you as a computer scientist don't have a phone??". I usually I don't say it out loud but in my head the answer is always "because I am a computer scientist I don't have a phone".

I've often wondered why I'm in such a tiny minority even among my CS peers...

Then again, at least over here in Europe, new cars will mandatorily have tracking devices built in, so perhaps my whole effort was kinda moot to begin with.