Redirected walking is a simple but trippy idea: what if a virtual reality game could trick you into walking in circles, while feeling like you were moving straight ahead? It’s the big trick behind ambitious "hyper-reality" project The Void, and something that university labs were working on for years before that. But it can be tough to explain in a way that feels clear and informative instead of hand-wavey. That’s one reason I like this video about building the "unlimited corridor," an experiment from the University of Tokyo and game engine company Unity Technologies that was showcased at last week’s Siggraph show. It’s basically two convex walls with a gap between them, but the clip shows precisely how it could feel like a whole series of hallways.

The other reason I like the video is because everyone involved looks so totally mesmerized by running their hands down a series of long, identical walls. Participants in the Siggraph demo would apparently "experience a VR search for confidential information in a skyscraper," which sounds like a lot of fun. But as far as I can tell, these folks are just taking a nice stroll in the world’s most boring Doom level — never meeting, never touching, in their private and infinite virtual worlds. On the bright side, that’s still one of the coolest walking simulators I’ve ever seen.

Update August 3rd, 6:00PM ET: Added attribution to Unity Technologies.