T-Mobile has run a few recent promotions for family plans with four or more lines, but what if you don't need that many? T-Mobile is starting a new promo tomorrow that might be just what you're looking for. The new (and unfortunately named) Data Gone Wild promo includes two lines with 6GB of data each for $80 per month.
T-Mobile explains the benefits of this plan in its usual over-the-top fashion. You get Binge On, Music Freedom, and all the other Uncarrier stuff. Tmo also points out that the similar Verizon plan has half as much data and costs $20 more. Keep in mind you'll have to finance a phone if you aren't already a T-Mobile customer, and that adds a few bucks to the bill.
This plan will only be available for a limited time, but T-Mobile didn't say how limited. It is actually a pretty good deal, so don't wait too long.