Today, Microsoft begins shipping the HoloLens to developers.
The augmented-reality headset was announced early last year, but this is the first time people outside Microsoft-controlled demos will get their hands on it.
Right now, it's only available to developers and enterprise users — essentially, only people who work for an organization executing a very specific mission, like a hospital or NASA, or are engineers building new tools and experiences for HoloLens and are in need of a headset to do it.
Even though the HoloLens is a ways away from making it onto the heads of average consumers, Microsoft is beginning to show off exactly what it's going to be used for when it does.
Case Western Reserve University will be using it for medical education and research.
NASA is using it to take a closer look at Mars and to stay connected with astronauts on the International Space Station.
And, in one of the few looks at what normal consumers can expect, this is what Skype will look like on HoloLens.
In September, Microsoft CEO Satya Nadella indicated that the consumer version of HoloLens could be about five years away.