Seeing DOOM for the first time in my buddy's residence room had that effect on me.
The thing is I knew the math for 3D CG, but more from an academic angle. I'd also been playing some true 3D games like LHX. I "knew" that what I was seeing was just impossible -- there was no way it could be that fast on that hardware.
So, simplifying the problem from 6DOF 3D to 2.5D made a world of difference.
I love the idea that I might be able to turn an impossible problem into something solvable if I just constrain myself to solving a subset.
Something to keep in mind when stakeholders want everything all at once, with no compromises. Compromise / prioritization is what makes cutting-edge technology possible.
It's hard to explain to those who were not around the revolutionary change that occurred when GLQuake + the Voodoo card came out.
It was one of the few 'holy shit' moments in my technological life. I knew then and there that everything changed going forward.