Just a couple of months ago, Google's Project Fi service became Google Fi, and upon dropping the "Project", the firm immediately took steps to make it more mainstream. While all GSM unlocked and T-Mobile phones already worked on the network, "official" support was added, which meant that you can now activate a device that's not officially made for Fi, rather than having to activate an official Fi device and swap the SIM card to another phone.
Another step that's being taken to go more mainstream is that you can now purchase a Google Fi SIM card at one of over 500 Best Buy locations, the company announced today on Reddit. The SIM cards will run you $9.99, which is $9.99 more than they cost if you have them shipped to you from Google, but they do come with a $10 service credit upon activation.
There are some limitations though. For one thing, Best Buy will only be selling talk and text SIMs, as data-only SIMs will still have to be obtained through Google. Best Buy employees also can't help you set it up; you're on your own. The SIM cards aren't available through Bestbuy.com either, and since they're only in a limited amount of Best Buy locations, you'll want to call your local store to see if they have them.
This is still notable though, as it's the first time that Google Fi has been pushed through a retailer. Previously, the only way to obtain Fi services was through Google's website.