[danbruc]

Fun fact: having nmap installed on your computer is illegal in Germany.

That does not sound right and I am unable to find any source for that claim.

EDIT: Nmap might fall under § 202c STGB [1] and »verschaffen« (obtain) probably does not even require installing it, downloading it would probably be sufficient. But my non-lawyer interpretation would be that this only applies if you are doing it for the purpose of a crime as it starts with »Wer eine Straftat nach § 202a oder § 202b vorbereitet, indem er [...]« (Who prepares a criminal act according to § 202a or § 202b by [...]).

https://www.gesetze-im-internet.de/stgb/__202c.html

[immibis]

Do you think the police, when they raid your house on some pretext, will accept your argument that it wasn't to prepare for a crime?

[danbruc]

Innocent until proven guilty, it is their job to show that I was preparing some crime, I would not make any arguments.

[immibis]

Having nmap on your computer and a plausible story from the police is sufficient proof of guilt.