The promotion is running through December 17.

Despite its hardware restrictions and potentially expensive data charges, Project Fi is still one of the most unique service providers around. Google's been continually adding new features and services since its debut in 2015, and a new promotion lets you grab a free Chromecast and Moto X4 for referring others to join.

Google launched a referral system for Project Fi last December that allowed you to get credits on your bill when new customers signed up with your referral code, and between now and December 17, you can use that same system for grabbing some new tech.

Making two successful referrals will allow you to get a free Chromecast, but making five more for a total of seven will grant you with a Moto X4. That's the Android One version of the Moto X4 that comes with a stock build of Android and fast software updates, and considering that it normally costs $399, this is a fantastic promotion if you're a Fi customer.

In addition to this, Project Fi is also donating $50,000 to the Information Technology Disaster Resource Center to help provide some relief for areas affected by this year's devastating hurricanes and other storms.

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