The sheer vastness of possibilities it creates. It's fascinating how literally incomprehensible degrees of complexity can be derived from NAND gates.

I imagine it is not distinct from the way a biologist, or even anyone considering a flower or bug or life in any form, might marvel at how simple cells (not that they are as simple as a NAND gate) can generate such diverse functionality.

I've never formally studied computer science so my knowledge is fairly simplistic as of yet, but currently I am fascinated by the way computation can aid the expression of geometric patterns. I recently learned about the epicycloid and have enjoyed exploring various algorithms for generating patterns with them.