The use of Bitcoin is also nearly tax-free, here, so long as you do not earn profits over the €1000 limit per year.

https://www.steuern.de/bitcoin-steuer#:~:text=Werden%20Bitcoins%20innerhalb%20eines%20Jahres,von%20Kryptow%C3%A4hrung%20kann%20steuerpflichtig%20sein.