Artist Tor Frick is the sole man responsible for the Unreal Engine tech demo you see above. If you just watch it, it looks lovely, but also looks like nothing out of the ordinary.
It's only when you find out he made it using a single 256x512 texture that you go "wow".
For reference, in most games an environment like the one in the video would be comprised of dozens, if not hundreds of textures. Yet by using just one, and selectively applying it to go with fancy lighting effects, he can dress an entire science lab in it.