Okay, I had forgotten about this, but since MP5 has stirred my memory about it, I thought I would put this out there. Years ago, before 3D VR was a popular thing, there was a technique of crossing your eyes to view images created for 3D without any hardware or glasses. To do this you need to get the images to be as large as possible and then sit back and cross your eyes until the two images merge in the middle. There will be two images off to either side (from your perspective), but the one in the middle will be in 3D. This takes a little practice, but years ago I used to look for, create and view images like this all the time. I also discovered that you could do it with video as well. I tested this one and yeah, you can get the 3D effect without any hardware. However, with a headset that uses a cell phone, it is then VR and full size.
MH