It's a bit different than what's discussed here, but color-contrast detectors in neural networks can be thought of as forming a Klein bottle: https://distill.pub/2020/circuits/equivariance/#hue-rotation...

(This is, in some sense, for similar reason to Gunnar Carlson et al finding a Klein bottle when looking at high-contrast image patches, except one level more abstract, since it's about features rather than data points.)