The PlayStation VR doesn't just work with the PlayStation 4. As it turns out, the virtual reality headset can actually accept any valid HDMI input, albeit without the full virtual reality experience.
When the PlayStation VR is connected to a regular HDMI output, such as an Xbox One, the headset displays content in a 'cinema mode.' In this mode, a large 2D screen covers most of your field of view, as if a cinema screen was positioned a meter or so from your face. Move your head and the screen stays in place.
The fact that the PSVR can accept inputs from any HDMI source gives it a leg up on its headset competitors, the HTC Vive and Oculus Rift. Both of these headsets are designed for PC games, and support non-VR content from a PC in a cinematic mode similar to the PSVR, however neither headset works with standard HDMI sources from a console or other device.
This extra functionality built in to the PSVR could make it a decent portable TV, or just another way to play games on a larger screen. Ars Technica reports that when using the PSVR's cinema mode, there "was no discernible display latency or lag that affected non-PlayStation gameplay" and "and the PSVR's included headphone jack handled audio from these external sources just fine, too".
Surely now it's only a matter of time before the PlayStation VR headset is hacked to work with PC games designed for Rift or Vive.