I just saw this, and it looks pretty good!
They have 1,3,6,12 month plans. You choose the data you want to buy, 2GB thru 10GB.
It's on T-Mobile network, which works great in my area (NY Metro).
Took the plunge into a 12 month 2GB for $21/month...sweet deal! Might upgrade later to 12 months 5GB for $365, that's a buck a day but let's see how it goes.
It seems to be an Ultra Mobile product, and they have been around a while now with good feedback.
Seems like a great deal?