The fair and flexible plan. I still have it for a couple of lines on my account. Unfortunately I can't use it for my own line because smart phones require "everything data" plans now.
That's one of the four reasons I don't have a not-so-smart phone. My wife and I have a voice plan that is more than enough for our combined needs. If Sprint would simply allow me to add data to one line, one obstacle to my having a phone with data would be removed.
Oh well... I save money, this way, so it's all good