Google just officially announced its virtual carrier, Google Fi. The pricing:
Project Fi takes a fresh approach to how you pay for wireless, manage your service, and get in touch when you need help. We offer one simple plan at one price with 24/7 support. Here’s how it works: for $20 a month you get all the basics (talk, text, Wi-Fi tethering, and international coverage in 120+ countries), and then it’s a flat $10 per GB for cellular data while in the U.S. and abroad. 1GB is $10/month, 2GB is $20/month, 3GB is $30/month, and so on. Since it’s hard to predict your data usage, you’ll get credit for the full value of your unused data. Let’s say you go with 3GB for $30 and only use 1.4GB one month. You’ll get $16 back, so you only pay for what you use.
The pricing scheme is very interesting, but it’s limited to US Nexus 6 owners for now. It intelligently switches between wifi, T-Mobile, and Sprint.