If I can’t be a number, none of you can!

(See also cascading nulls)

In Kerbal Space Program your ships sometimes catch the NaN virus. If one fuel tank level is reading NaN then whatever you do DON’T try and fill it from another (full) tank. I’m not sure if it can spread to physics (thrust, mass, etc) but I presume that it can given that fuel tank mass is calculated based off filled capacity.

I wonder what would happen if you landed a NaN-infected spaceship on a planet.

for the math homies, you could say that NaN is an absorbing element

It’s infectious!