the Cray supercomputer was designed while Seymour dug a tunnel: Another favorite pastime was digging a tunnel under his home; he attributed the secret of his success to "visits by elves" while he worked in the tunnel: "While I'm digging in the tunnel, the elves will often come to me with solutions to my problem."
More acting weirdly for ads and profit from what I gather there. Does he actually dig a tunnel / have someone dig a tunnel for him (like he has others cut out the concrete slab etc.) or does it stay at the stage of a hatch set on top of dirt?
I am also reluctant to invest time in watching a video, but he is quite impressive, at least to me. Starting out several years ago, he is digging by hand with the aid of a hydraulic poker that he fashioned. Removing the dirt and stones in buckets, welding reinforcing structure as he goes, etc.
https://en.wikipedia.org/wiki/Seymour_Cray