I just don't get your point about avoiding a cell phone because you don't want to pay a monthly plan. We all do this with water, energy, internet. If you really do not use a phone I understand. But in my case, I have a cheap smartphone and a prepaid plan. I spend literally less than 1 dollar a month (make less than 4 calls a month) in it and I keep the same number for over a decade just to receive calls. I connect using 3G 3 or 4 times a year! And I pay 1 dollar to connect for a whole day, when I want. But I keep a smartphone because every week I receive 2 or 3 calls, it was extremely useful and required to get a job as I don't have a landline. The smartphone functions on it are really basic. I receive instant messages and check daily for updates, I check .pdf files, GPS when I go to a city I don't know anything about, email, alarm clock, instant message (whatsapp) and MP3 player and podcasts hub. I connect only at wi-fi spots and I don't ever plan to have a data plan.

I already tried to live without a phone for 3 months. It was awkward to ask people around to use their phones to call for a cab after hanging out at night. And in this experiment I simply did not receive calls from friends. Setting a date or appointment and waiting hours till the person appears, if she couldn't get on time, a simply cal would solve this. Luckily I had no accident with the car or get robbed while in this experiment, a cellphone would come in handy.

I've tried both sides of the coin, and I do prefer to have a phone to receive calls and to use as mp3 player, than no phone at all. Getting a landline and pay at least 30 times more than I pay monthly on my phone, to use it only when at home, is not really an option.