Sprint is offering their loyal customers some fairly substantial discounts for the holidays, including discounted device leasing, free service, and accessory discounts. Of course, it's Sprint defining "loyal" here, though customers that have been deemed worthy of the title have started receiving emails about the offers. Here's what Sprint's offering…
A 16GB iPhone 6 or Samsung Galaxy S5 for just $5 a month and $0 down; normally they're both $20 monthly (that's $360 off over the 2-year course of payments).
You can add a new line, pay the remainder of the current month, and then get that line of service free of charge for 12 months, all with unlimited talk, messaging, and data.
For legacy plans with limited voice minutes, you can now get unlimited voice minutes within the U.S. (like any modern plan).