On: Calculus Is Deeply Irrational

[proc0]

Looks like black metal band logo. Brutal function.

[ska → proc0]

You might also like the Cantor function, which is also known as "The Devils Staircase"

It is similarly used as an example, for a function that is continuous but not absolutely continuous.

cfL https://en.wikipedia.org/wiki/Cantor_function

[lanstin → ska]

If you like these sorts of things, there is a slim tome called "Counterexamples in Topology" which is very long list of similar weird things.