AT&T Advice
I’m very sorry for the specific nature of this post: it’s only for those using AT&T for cell service (most likely iPhone users).
I just discovered, after five months of AT&T service, that they have a feature called “A-List” that’s free for most accounts, but deactivated by default. (dicks)
A-List is one of those “My Circle” type promotions where you can add up to five phone numbers to your “A-List” and then send and receive calls to those numbers without accruing minutes.
To add this feature, you need to log-in to your online account and then choose “Add Features” under “My Services.”
Bonus advice: If you use Google Voice for inbound/outbound calls, you can add this number to your “A-List” and have all calls routed through your GV account absolutely free.