A bit of VR history here - A free VR system developed in 1991 by two enthusiasts that ran on PCs and was compatible with the Nintendo Power Glove and the SegaScope shutterglasses:
In the first half of the 1990s there had been a huge mediatic boom about virtual reality. Movies about VR were released; TV programmes were hyping incredibly expensive hardware; books about the phylosophy of the virtual were written; everyone was talking about virtual reality.
All the hype was basically just a lot of talking, until two independent VR enthusiasts, Dave Stampe and Bernie Roehl, decided that it was time to actually bring virtual reality to PC users. For this reason, they wrote an open source software for MS-DOS they called Rend386 that allowed the creation and exploration of virtual worlds and offered native support to the Nintendo Power Glove (for manipulation) and the SegaScope shutterglasses (for stereoscopy). Rend386 and its successors VR386 and AVRIL were quite popular on FidoNet and on the internet, and some users created free virtual environments for them.
Here is a YouTube video (in Italian - turn captions on) which explains and demonstrates more:
If you are happy to download a browser add-on, you can view some of the 3D worlds created from this time.
More info can be found here