Free data sounds like a good thing, but a new article from net neutrality icon Susan Crawford says a new breed of partially free data plans could spell doom for the open web. Crawford's target is zero-rating, a system that lets content companies buy out specific portions of a given user's data plan, offering effectively free data as long as you're using the right apps. Under this system, Google might pay AT&T to make YouTube exempt from any data caps, giving AT&T customers the chance to go wild with video consumption, but also shutting smaller competitors like Vimeo out of the picture entirely.

As Crawford points out, that's not how net neutrality works. Once carriers start discriminating between different services and making money off it, the internet may not stay open very long. The practice has already been banned in a number of countries, but new plans from AT&T and Sprint show the idea is alive and well in the US, with potentially troubling consequences for anyone trying to compete with a major web company. "Can you imagine trying to launch a competitor to Facebook in a country where most of your potential customers will have to pay data charges for your service—while the incumbent Facebook is exempt?" Crawford writes. If the trend continues, we may not need to imagine it at all.