yes, 83c per month is not a joke although I don't see how it relates to AIO discussion.
TMobile has a prepaid voice/text only service called TMobileToGo where, after you spend $100 with them, they allow you to keep the number for $10 a year. That $10 buys you 35mins/texts. Great for emergency, backup and rare usage (kids, elders, etc). BTW, a one time expense of $100 buys you 1000 min and is good for 1y and can be used on TMO, ATT and in Canada (Rogers- expensive but works).